ASUS
ASUS X412F C21N1818-2 Laptop Battery – 37Wh, 7.7V Replacement
- SKU:
- W126717652
- UPC:
- 5704174970637
- MPN:
- 0B200-03280700
- Availability:
- UK mainland delivery: 2–3 working days (Monday–Friday, excluding bank holidays). Free collection in Peterborough: please wait for your ready-to-collect message.
Description
Genuine ASUS C21N1818-2 Laptop Battery – 37Wh 7.7V 0B200-03280700 for X412F, X415 & X515
The ASUS C21N1818-2 laptop battery, manufacturer part number 0B200-03280700, is a genuine ASUS internal replacement battery designed for selected ASUS VivoBook and Notebook models including the X412F, X415 and X515 families. It provides a manufacturer-rated 37Wh energy capacity, 7.7V nominal voltage and 2S1P lithium-polymer battery configuration.
This genuine ASUS service part is designed to replace a worn, ageing or failed C21N1818-2 battery while maintaining the correct physical fit, electrical connection and battery specification required by compatible ASUS laptops.
ASUS's own service documentation identifies the battery as C21N1818-2 / 2S1P / 7.7V / 37Wh, while ASUS Parts lists the exact service SKU 0B200-03280700 for the X412F battery assembly.
Quick answer: The ASUS 0B200-03280700 is a genuine internal C21N1818-2 replacement battery rated at 37Wh and 7.7V. It uses a 2S1P lithium-polymer configuration and is designed for selected ASUS X412F, X415, X515, P1412CEA and P1512CEA laptops. Always confirm the original battery label or ASUS service part number before purchasing because visually similar C21N1818 battery variants exist.
Key Features of the ASUS C21N1818-2 Battery
- Genuine ASUS internal replacement battery
- ASUS service part number: 0B200-03280700
- Battery model: C21N1818-2
- Designed for selected ASUS X412F, X415, X515 and related Notebook models
- 37Wh energy capacity
- 7.7V nominal voltage
- Rechargeable lithium-polymer battery pack
- 2S1P battery configuration
- Internal laptop battery design
- Black battery casing
- Direct replacement for compatible ASUS factory battery installations
- Designed to connect to the laptop's existing internal battery connector
- ASUS repair documentation shows three battery-retaining screws on supported X415 chassis
- Suitable for replacing an ageing or failed original battery
- Can help restore portable laptop operation when the original battery has degraded
- ASUS-branded service component rather than a generic aftermarket battery
- Rechargeable design
- CE and RoHS compliance listed by current UK distributor data
- Quantity: 1 internal laptop battery
Genuine ASUS 0B200-03280700 Service Battery
This product is not simply a third-party battery advertised as compatible with ASUS laptops.
The exact manufacturer part number 0B200-03280700 is listed by ASUS Parts as:
X412F BATT/COS POLY/C21N1818-2
This makes it a genuine ASUS replacement/service component intended for compatible ASUS notebook configurations that were originally designed around this battery assembly.
Why the ASUS Part Number Matters
Laptop batteries are highly model-specific. Two batteries can have similar capacities and voltages while still differing in:
- Physical shape
- Mounting points
- Battery connector
- Connector position
- Cable length
- Battery management electronics
- Firmware communication
Matching the exact ASUS service part number is therefore one of the safest ways to identify the correct replacement.
ASUS Battery Model C21N1818-2
The internal battery model used by this product is:
C21N1818-2
ASUS service documentation identifies this exact battery model in compatible X415-series systems, while ASUS Parts directly associates the same battery with the X412F platform.
Do Not Confuse C21N1818-2 with Similar Battery Variants
Several similarly named ASUS batteries can be found online, including:
- C21N1818
- C21N1818-1
- C21N1818-2
- Other C21N1818-family revisions
These names should not automatically be treated as interchangeable.
Different revisions can have different physical housings, connector arrangements or electrical specifications. For this product, the strongest compatibility reference is:
ASUS part number 0B200-03280700 / battery model C21N1818-2.
37Wh Energy Capacity
ASUS officially specifies this battery pack with an energy rating of:
37Wh
Watt-hours indicate the total electrical energy that the battery is designed to store when new.
A replacement 37Wh battery can help restore portable operation if the original battery has deteriorated and now provides only a fraction of its original runtime.
Why Wh Is More Useful Than mAh Alone
Watt-hours account for both battery capacity and voltage, making Wh the most reliable specification when comparing laptop battery energy.
For this exact ASUS service part, the manufacturer-confirmed specifications to prioritise are:
- 37Wh
- 7.7V
- 2S1P
- C21N1818-2
Important mAh Capacity Clarification
Current distributor databases show slightly different amp-hour figures for this ASUS service part. Some listings quote approximately 4730mAh, while others use approximately 4850mAh.
Because ASUS's own service documentation identifies the battery primarily by its 37Wh / 7.7V rating, those manufacturer-confirmed values are the most reliable specifications to use when checking compatibility.
For this reason, buyers should not reject or select a battery solely because two reseller listings show slightly different rounded mAh figures.
7.7V Nominal Battery Voltage
The ASUS C21N1818-2 has a manufacturer-specified nominal voltage of:
7.7V
The replacement battery should match the laptop's required battery voltage and battery assembly rather than being chosen simply because another battery looks physically similar.
Always Check the Existing Battery Label
Before ordering, check the original battery inside the laptop for:
- C21N1818-2
- 0B200-03280700
- 7.7V
- 37Wh
If these details match, this provides a strong indication that you have identified the correct ASUS replacement battery.
2S1P Battery Configuration
ASUS's official repair documentation identifies the C21N1818-2 as a:
2S1P battery pack
This means the battery uses two cell groups connected in series with one parallel path.
In practical terms, this is a two-cell-class internal battery configuration engineered to provide the required 7.7V nominal output.
Lithium-Polymer Battery Technology
The C21N1818-2 is specifically identified in ASUS service documentation as POLY, and the battery manufacturer's safety documentation describes it as a:
Rechargeable Li-Polymer Battery Pack / 2S1P
Lithium-polymer technology allows manufacturers to produce thin internal battery packs shaped to fit compact laptop chassis.
Lithium-Polymer Is Part of the Lithium-Ion Family
Some distributor catalogues classify this product generically as Lithium-Ion / Li-Ion.
This is not necessarily contradictory: lithium-polymer batteries are part of the broader rechargeable lithium-ion family, but Li-Polymer is the more precise construction description for this exact C21N1818-2 pack.
Designed for ASUS VivoBook X412F
ASUS Parts directly identifies manufacturer part number 0B200-03280700 as an:
X412F C21N1818-2 battery
This makes the X412F one of the primary laptop platforms associated with the battery.
ASUS VivoBook 14 X412 Series
The C21N1818 battery family can appear across several VivoBook 14 configurations, but ASUS laptops within the same X412 family can still use different battery revisions.
Always confirm that the installed battery is specifically C21N1818-2 / 0B200-03280700.
Compatible ASUS X415 Series
Current ASUS and UK distributor data also lists the C21N1818-2 / 0B200-03280700 for selected X415 configurations including:
- ASUS X415DA
- ASUS X415EA
- ASUS X415EP
- ASUS X415FA
- ASUS X415JA
- ASUS X415JF
- ASUS X415JP
- ASUS X415KA
- ASUS X415MA
- ASUS X415UA
Compatibility can vary by full laptop SKU, so checking the original battery remains recommended.
Compatible ASUS X515 Series
Current UK supplier data lists the battery for selected X515 models including:
- ASUS X515DA
- ASUS X515EA
- ASUS X515EP
- ASUS X515FA
- ASUS X515JA
- ASUS X515JF
- ASUS X515JP
- ASUS X515KA
- ASUS X515MA
- ASUS X515UA
Compatible ASUS P-Series Models
Current distributor compatibility data also lists:
- ASUS P1412CEA
- ASUS P1512CEA
Again, always confirm the full laptop SKU or battery label before ordering because a notebook family can contain different internal hardware revisions.
Additional ASUS Regional Model Names
ASUS itself lists the same 0B200-03280700 C21N1818-2 service battery for selected regional equivalents in families including:
- ASUS M415
- ASUS M515
- ASUS X1400
- ASUS X1500
- ASUS P1411
- ASUS P1511
These model families can use different suffixes depending on country and hardware configuration, so compatibility should be confirmed from the exact model number or original battery part number.
Ideal Replacement for a Worn ASUS Laptop Battery
Rechargeable laptop batteries gradually lose usable capacity as they age.
Replacement may be worth considering if your ASUS laptop:
- Runs for only a short time away from the charger
- Turns off unexpectedly at a reported battery percentage
- Loses charge unusually quickly
- No longer charges fully
- Displays a battery health warning
- Only operates reliably when connected to mains power
- Has a physically swollen battery
Battery Runtime Naturally Declines with Age
Rechargeable batteries are consumable components.
Each charge and discharge cycle contributes gradually to chemical ageing, so a battery that originally provided several hours of use may eventually provide much less runtime even when the laptop itself is still working correctly.
Restore Portable Laptop Use
Replacing a degraded battery can often be more economical than replacing an otherwise functional laptop.
A correctly matched replacement can help restore:
- Portable working
- Study away from a charger
- Meeting-room use
- Travel use
- Battery backup during brief power interruptions
Actual Runtime Depends on the Laptop
The 37Wh rating does not translate into a fixed number of runtime hours.
Battery life varies according to:
- Processor load
- Screen brightness
- Display size
- Wi-Fi usage
- Bluetooth usage
- SSD / storage activity
- Connected USB devices
- Video playback
- Background applications
- Windows power settings
- Battery calibration
- Laptop age and condition
For this reason, exact battery runtime should not be guaranteed from the Wh rating alone.
Internal Laptop Battery
The C21N1818-2 is an internal battery.
It is located underneath the laptop's bottom cover and is not designed to be removed externally during everyday use.
Installation Requires Opening the Laptop
ASUS's own repair documentation shows that compatible X415-series laptops require the bottom cover to be removed before accessing the battery.
The battery connector must be disconnected before the battery module is removed.
Three Battery Retaining Screws on ASUS X415 Service Design
ASUS repair documentation for supported X415 models shows the C21N1818-2 secured with three M2 × 5mm screws.
Other compatible chassis revisions may differ, so always follow the service instructions for the exact laptop model being repaired.
Professional Installation Recommended if Unsure
Replacing an internal battery is straightforward for an experienced repair technician, but incorrect installation can damage:
- Battery connector
- Motherboard socket
- Bottom cover clips
- Internal cables
- Battery pack
If you are not comfortable opening a laptop, professional installation is recommended.
Important Battery Safety
Never continue using a battery that is:
- Swollen
- Punctured
- Leaking
- Overheating
- Cracked
- Physically deformed
A swollen lithium battery can place pressure on the laptop chassis, keyboard, touchpad or display assembly.
Disconnect Power Before Installation
Before replacing an internal laptop battery:
- Shut down the laptop fully
- Disconnect the AC charger
- Disconnect external devices
- Follow appropriate ESD precautions
- Disconnect the internal battery connector before servicing other internal parts
Responsible Battery Recycling
Lithium-polymer laptop batteries should not be placed in normal household waste.
Old or failed batteries should be taken to an appropriate battery or electrical recycling collection point.
Do not:
- Puncture the battery
- Crush the battery
- Burn the battery
- Short the terminals
- Expose the battery to excessive heat
Battery Calibration After Installation
After a replacement battery is installed, the laptop's reported battery percentage may sometimes require a small number of normal charge and discharge cycles to settle.
This does not necessarily indicate a battery fault.
Recommended Initial Use
After installation:
- Connect the normal ASUS-compatible charger
- Allow the battery to charge fully
- Use the laptop normally
- Allow Windows battery reporting to recalibrate naturally over several normal cycles
Avoid deliberately deep-discharging lithium batteries to 0% repeatedly, as this is not required for routine calibration and can accelerate battery wear.
How to Check Battery Health in Windows
Windows users can create a battery health report using the built-in powercfg tool.
A battery report can help compare:
- Original design capacity
- Current full-charge capacity
- Recent battery usage
- Battery capacity history
- Estimated runtime
If the existing battery's full-charge capacity has fallen substantially below its original design capacity, replacement may improve portable runtime.
How to Confirm Compatibility Before Ordering
For the most reliable match, check the original battery inside the laptop.
Look for C21N1818-2
The existing battery should ideally display:
C21N1818-2
Look for ASUS Part Number 0B200-03280700
The strongest exact part reference for this Memox product is:
0B200-03280700
Compare Voltage and Capacity
The ASUS service specification is:
- Voltage: 7.7V
- Energy: 37Wh
Compare Physical Shape and Connector
The battery should also match the:
- Physical outline
- Mounting-hole positions
- Cable orientation
- Battery connector
If your battery label shows a different C21N1818 revision, do not assume compatibility without checking the exact ASUS laptop SKU.
ASUS C21N1818-2 Technical Overview
- Brand: ASUS
- Product Type: Genuine internal laptop replacement battery
- Battery Model: C21N1818-2
- ASUS MPN / Service Part: 0B200-03280700
- Memox SKU: W126717652
- EAN / GTIN-13: 5704174970637
- Battery Energy: 37Wh
- Nominal Voltage: 7.7V
- Battery Technology: Rechargeable Lithium-Polymer / Li-Polymer
- Broader Chemistry Family: Lithium-Ion
- Configuration: 2S1P
- Cell Configuration: Two-cell-class series configuration
- Battery Position: Internal
- Product Colour: Black
- Rechargeable: Yes
- Primary ASUS Platform: X412F
- Selected Additional Families: X415 / X515 / P1412CEA / P1512CEA
- Quantity: 1 battery
- Laptop Included: No
- Charger Included: No
Important C21N1818 Variant Note
C21N1818-2 is the exact battery revision supplied on this page.
Do not automatically treat C21N1818, C21N1818-1, C21N1818-2 and other similarly named packs as identical.
Check the original battery part number, ASUS service part number, shape, voltage and connector before ordering.
Important 37Wh / 7.7V Specification Note
ASUS's own repair documentation specifically identifies the C21N1818-2 as:
2S1P / 7.7V / 37Wh
These are the preferred manufacturer specifications for this exact service part.
Important mAh Specification Note
Reseller databases currently disagree slightly on the mAh value for 0B200-03280700, with figures around 4730mAh to 4850mAh appearing online.
To avoid creating an inaccurate specification, the manufacturer-confirmed 37Wh and 7.7V values should take priority.
For SEO and customer compatibility checking, I recommend displaying 37Wh prominently rather than relying on a disputed rounded mAh number.
Important Chemistry Note
ASUS service documentation identifies the battery as POLY, and the pack manufacturer's safety documentation describes C21N1818-2 as a Rechargeable Li-Polymer Battery Pack.
Some supplier catalogues use the broader description Lithium-Ion. Both belong to the rechargeable lithium-ion family, but Lithium-Polymer is the more precise description for this exact pack.
Important Compatibility Note
This battery is not a universal ASUS laptop battery.
ASUS uses different battery packs across notebooks that may share similar product names.
Always check the original battery label or full laptop SKU before purchase.
Important X412F Compatibility Note
ASUS's own parts store explicitly identifies part number 0B200-03280700 as an:
X412F C21N1818-2 battery.
This provides direct manufacturer confirmation for the X412F application.
Important Installation Note
This is an internal service component that requires removal of the laptop base cover.
If you are not familiar with laptop disassembly, professional installation is recommended.
Important Runtime Note
The 37Wh rating does not guarantee a specific number of operating hours.
Runtime depends on laptop configuration, battery health, screen brightness, processor usage, wireless connectivity, attached devices and operating-system power settings.
Important Barcode Note
The barcode currently stored by Memox as 5704174970637 contains 13 digits.
It should therefore be treated as an EAN / GTIN-13, rather than a 12-digit UPC.
Who Is the ASUS C21N1818-2 Battery Best For?
- ASUS X412F owners requiring the correct genuine service battery
- Selected ASUS X415-series laptop owners
- Selected ASUS X515-series laptop owners
- Selected ASUS P1412CEA / P1512CEA owners
- Users replacing an ageing C21N1818-2 battery
- Repair technicians servicing compatible ASUS laptops
- Users who want a genuine ASUS service part instead of a generic replacement
- Users whose laptop has poor portable runtime
- Users replacing a failed or swollen original battery
Who Should Consider a Different Battery?
Do not purchase this battery if:
- Your original battery uses a different ASUS service part number
- Your original pack has a different physical design
- Your battery connector is in a different location
- Your laptop requires a different voltage
- Your laptop uses another C21N1818 family revision that has not been confirmed as compatible
- Your ASUS laptop model is not listed and the battery part number cannot be verified
Why Choose the Genuine ASUS C21N1818-2 Battery?
The ASUS C21N1818-2 0B200-03280700 is an original ASUS service battery designed around the electrical and physical requirements of compatible ASUS notebooks.
Its manufacturer-confirmed 37Wh energy rating, 7.7V nominal voltage and 2S1P lithium-polymer configuration match ASUS service documentation for the C21N1818-2 battery assembly.
Unlike generic batteries that may only claim compatibility with a broad laptop family, this product carries the exact ASUS service part number 0B200-03280700, making it easier to match against the original component installed in the laptop.
ASUS directly associates the part with the X412F, while current ASUS and UK distribution data also identifies compatibility with selected X415, X515 and P-series notebook configurations.
Replacing a degraded original battery can help restore portable laptop use, reduce dependence on the mains charger and extend the useful life of an otherwise functional ASUS notebook.
Choose the ASUS C21N1818-2 if your compatible ASUS laptop uses service part 0B200-03280700 and you need a genuine 37Wh, 7.7V internal replacement battery.
Specification
ASUS C21N1818-2 37Wh 7.7V Laptop Battery Specifications
The ASUS C21N1818-2, manufacturer service part 0B200-03280700, is a genuine internal rechargeable battery for selected ASUS X412F, X415, X515 and related notebook models. ASUS service documentation specifies the battery as a 2S1P, 7.7V, 37Wh lithium-polymer battery pack.
General Information
| Brand | ASUS |
| Product Type | Internal Laptop Replacement Battery |
| Battery Model | C21N1818-2 |
| Manufacturer Part Number / MPN | 0B200-03280700 |
| ASUS Service Description | X412F BATT/COS POLY/C21N1818-2 |
| Memox SKU | W126717652 |
| Condition | New |
| Part Quality | Genuine / Original ASUS Service Part |
| Product Colour | Black |
| Quantity | 1 Battery |
Battery Electrical Specifications
| Battery Energy Capacity | 37Wh |
| Nominal Voltage | 7.7V |
| Battery Configuration | 2S1P |
| Cell Configuration | 2-Cell |
| Rechargeable | Yes |
| Battery Position | Internal |
| Hot-Swappable | No |
Battery Chemistry
| Battery Technology | Lithium-Polymer / Li-Polymer |
| Broader Chemistry Family | Lithium-Ion |
| ASUS Service Description | POLY |
| Battery Manufacturer Safety Description | Rechargeable Li-Polymer Battery Pack / 2S1P |
Manufacturer Battery Identification
| ASUS Battery Model | C21N1818-2 |
| ASUS Customer Part Number | 0B200-03280700 |
| ASUS Service Reference | X412F BATT/COS POLY/C21N1818-2 |
| Battery Pack Manufacturer Reference | SMP / CA615383G |
| Battery Configuration Reference | 2S1P / 7.7V / 37Wh |
Primary ASUS Compatibility
| ASUS X412F | Compatible – ASUS directly identifies 0B200-03280700 as an X412F C21N1818-2 battery |
| ASUS X415 Series | Compatible with selected models listed below |
| ASUS X515 Series | Compatible with selected models listed below |
| ASUS P-Series | Compatible with selected P1412CEA and P1512CEA models according to current UK distributor data |
ASUS X415 Series Compatibility
| X415DA | Compatible |
| X415EA | Compatible |
| X415EP | Compatible |
| X415FA | Compatible |
| X415JA | Compatible |
| X415JF | Compatible |
| X415JP | Compatible |
| X415KA | Compatible |
| X415MA | Compatible |
| X415UA | Compatible |
ASUS X515 Series Compatibility
| X515DA | Compatible |
| X515EA | Compatible |
| X515EP | Compatible |
| X515FA | Compatible |
| X515JA | Compatible |
| X515JF | Compatible |
| X515JP | Compatible |
| X515KA | Compatible |
| X515MA | Compatible |
| X515UA | Compatible |
ASUS P-Series Compatibility
| P1412CEA | Compatible according to current UK distributor data |
| P1512CEA | Compatible according to current UK distributor data |
Additional ASUS Regional Compatibility
| M415 Series | Selected models officially listed by ASUS regional parts data |
| M515 Series | Selected models officially listed by ASUS regional parts data |
| X1400 Series | Selected models officially listed by ASUS regional parts data |
| X1500 Series | Selected models officially listed by ASUS regional parts data |
| P1411 Series | Selected regional models listed by ASUS |
| P1511 Series | Selected regional models listed by ASUS |
Installation Type
| Installation Location | Inside Laptop Chassis |
| Laptop Bottom Cover Removal Required | Yes |
| Battery Connector | Internal ASUS Laptop Battery Connector |
| Plug-and-Play External Battery | No |
| Professional Installation Recommended | Yes if the user is unfamiliar with laptop disassembly |
ASUS X415 Service Installation Details
| Battery Retaining Screws | 3 on the ASUS X415 service chassis documented by ASUS |
| Screw Specification | M2 × 5mm |
| Battery Removal | Bottom case and battery connection must be accessed internally |
| Important | Exact installation procedure can vary by laptop SKU |
Battery Capacity Information
| Manufacturer-Confirmed Energy Rating | 37Wh |
| Manufacturer-Confirmed Voltage | 7.7V |
| mAh Capacity | Not stated here because current distributor databases provide conflicting 4730mAh and 4850mAh values |
| Recommended Compatibility Reference | 37Wh / 7.7V / C21N1818-2 / 0B200-03280700 |
Battery Weight
| Current Distributor Battery Weight | Approximately 185g in current UK product data |
| Manufacturer-Confirmed Bare Battery Weight | Not consistently published by ASUS for this service part |
| Recommendation | Use the weight only as an approximate distributor specification, not as a compatibility criterion |
Colour and Construction
| Colour | Black |
| Form | Flat Internal Laptop Battery Pack |
| Device-Specific Design | Yes |
| Universal Laptop Battery | No |
Transport Classification
| Battery Transport Family | Lithium-Ion / Lithium-Polymer Rechargeable Battery |
| Current UK Distributor ADR Classification | UN3480 – Lithium Ion Batteries |
Package Contents
| ASUS C21N1818-2 Battery | 1 |
| Laptop | Not Included |
| AC Charger | Not Included |
| Installation Service | Not Included |
Product Identification
| Manufacturer | ASUS |
| Battery Model | C21N1818-2 |
| Manufacturer Part Number | 0B200-03280700 |
| Memox SKU | W126717652 |
| Memox / UK Distributor EAN / GTIN-13 | 5704174970637 |
| Energy Capacity | 37Wh |
| Voltage | 7.7V |
| Configuration | 2S1P |
Warranty
| Current UK Distributor Warranty | 3 Months |
| Warranty Source | Current EET UK product data |
| Regional ASUS Warranty | May vary by country and sales channel |
| UK Statutory Rights | Not affected by manufacturer or distributor warranty wording |
Important Exact Part Number Note
The strongest compatibility identifier for this battery is the ASUS service part number:
0B200-03280700
ASUS directly identifies this part as:
X412F BATT/COS POLY/C21N1818-2
If your original battery carries the same ASUS part number, this provides the strongest indication of an exact replacement match.
Important Battery Model Note
The battery model supplied on this page is:
C21N1818-2
Do not assume that every battery labelled C21N1818, C21N1818-1 or another C21N1818 revision is electrically and physically identical.
Always check the complete battery model, ASUS service part number, voltage, capacity, physical shape and connector before ordering.
Important 37Wh / 7.7V Note
ASUS's own service documentation specifies the C21N1818-2 battery as:
- Battery configuration: 2S1P
- Nominal voltage: 7.7V
- Energy capacity: 37Wh
These manufacturer-confirmed specifications should take priority over generic third-party battery listings.
Important mAh Capacity Note
Current product databases disagree on the amp-hour capacity of ASUS part 0B200-03280700.
Figures of approximately 4730mAh and 4850mAh are both currently published for the same ASUS service part.
Because ASUS's own service documentation unambiguously identifies the pack as 37Wh / 7.7V, Memox should use those values as the primary capacity specification rather than publishing a disputed mAh figure.
Important Chemistry Note
ASUS uses the service description POLY for this battery, while the battery manufacturer's safety information identifies C21N1818-2 as a rechargeable Li-Polymer battery pack.
Some IT distributor databases categorise the battery more generally as Lithium-Ion.
The clearest specification for customers is:
Lithium-Polymer / Li-Polymer rechargeable battery, within the broader lithium-ion battery family.
Important X412F Compatibility Note
ASUS directly associates 0B200-03280700 with the X412F platform.
This is stronger evidence than generic compatibility lists from aftermarket battery sellers.
Important X415 / X515 Compatibility Note
Current UK distributor data lists 0B200-03280700 for selected X415 and X515 notebook configurations.
However, ASUS laptop families can contain multiple hardware revisions. Customers should still check their original battery label or complete laptop SKU before purchase.
Important P-Series Compatibility Note
Current UK distribution data lists P1412CEA and P1512CEA.
ASUS regional service listings also contain related P1411 / P1511 configurations, demonstrating that regional model naming can differ.
For this reason, the exact battery/service part number should take priority over a broad laptop-family name.
Important Installation Note
This is an internal laptop battery.
Installing it requires removal of the laptop's bottom cover and disconnection of the internal battery connector.
ASUS documentation for the compatible X415 service chassis shows the battery secured by three M2 × 5mm screws, but the precise installation procedure may vary by laptop SKU.
Important Battery Safety Note
Do not install or continue using a lithium battery that is swollen, leaking, punctured, overheated or physically damaged.
Before servicing the laptop:
- Shut the computer down completely
- Disconnect the AC charger
- Disconnect external peripherals
- Use appropriate anti-static precautions
- Disconnect the internal battery before servicing other internal components
Important Runtime Note
A 37Wh battery does not guarantee a specific number of hours of laptop use.
Actual battery life depends on factors including processor workload, display brightness, wireless activity, storage activity, connected devices, operating-system settings and the configuration of the laptop.
Important Weight Note
The current UK distributor database lists approximately 185g as the battery weight, while other reseller databases publish different values.
Because ASUS does not consistently publish a bare-product weight for this service part, weight should not be used as a primary compatibility check.
Important EAN / GTIN Note
Memox currently uses:
5704174970637
This is a 13-digit EAN / GTIN-13 associated with the product in the current UK distributor feed.
Other ASUS spare-parts channels may use different distribution barcodes for the same ASUS service part, so 0B200-03280700 remains the primary product identifier.
Important Warranty Note
The current EET UK distributor record lists a 3-month vendor warranty for this service component.
ASUS warranty terms for spare batteries can vary between countries and sales channels, so a regional warranty figure from another country's ASUS store should not automatically be presented as the UK manufacturer warranty.
Compatibility Check Before Purchase
Before ordering, compare the original battery or ASUS service information against the following:
- Battery model: C21N1818-2
- ASUS service part: 0B200-03280700
- Voltage: 7.7V
- Capacity: 37Wh
- Configuration: 2S1P
- Physical battery shape
- Connector location
- Mounting points
Matching the exact ASUS service part number is preferable to selecting a replacement using laptop family name alone.
Model Identification Note
These specifications apply specifically to the genuine ASUS C21N1818-2 internal laptop battery, ASUS service part 0B200-03280700, rated 37Wh, 7.7V, 2S1P, Memox SKU W126717652.
Return
FAQ: Frequenlty Asked Questions
ASUS C21N1818-2 37Wh 7.7V Laptop Battery FAQ
The ASUS C21N1818-2 / 0B200-03280700 is a genuine internal 37Wh, 7.7V rechargeable battery designed for compatible ASUS VivoBook, X Series and P Series notebooks. ASUS identifies this spare part as an X412F C21N1818-2 battery, while compatibility also extends to selected X415, X515, P1412 and P1512 models that use this exact battery specification.
Below are answers to the most common questions buyers ask about the ASUS C21N1818-2, including X412F, X415 and X515 compatibility, C21N1818 vs C21N1818-1 vs C21N1818-2 differences, B21N1818 compatibility, 37Wh capacity, battery installation, charging problems, Windows battery health reports, ASUS Battery Health Charging, battery lifespan, swelling and how to verify the correct replacement before ordering.
1. What is the ASUS C21N1818-2 battery?
The ASUS C21N1818-2 is an internal rechargeable laptop battery used in selected ASUS notebooks. This exact version is rated at 7.7V and 37Wh and is supplied under ASUS spare-part number 0B200-03280700.
2. What is the exact ASUS part number, SKU and EAN?
The ASUS manufacturer part number is 0B200-03280700, the battery model is C21N1818-2, the Memox SKU is W126717652 and the EAN is 5704174970637.
3. What are the main specifications of the C21N1818-2?
The key specifications are 37Wh energy capacity, 7.7V nominal voltage, 2S1P battery configuration, rechargeable lithium-ion polymer construction and an internal notebook battery form factor. It is designed for compatible ASUS laptops using this specific battery revision and connector layout.
4. Is this a genuine ASUS battery?
Yes. The manufacturer part number 0B200-03280700 appears in ASUS's own parts catalogue as the X412F C21N1818-2 battery. This distinguishes it from generic third-party batteries that merely claim compatibility with C21N1818-series laptops.
5. Is the C21N1818-2 lithium-ion or lithium-polymer?
ASUS identifies the pack as a polymer-based rechargeable lithium battery. It can therefore be described as a lithium-ion polymer / Li-polymer battery pack rather than a traditional removable cylindrical-cell laptop battery.
6. What does 37Wh mean?
37Wh means 37 watt-hours and describes the battery's stored energy capacity. Watt-hours are generally more useful than mAh when comparing laptop batteries because Wh takes both capacity and voltage into account.
7. What voltage is the original C21N1818-2 battery?
The exact ASUS C21N1818-2 / 0B200-03280700 is rated at 7.7V. When replacing an internal laptop battery, the safest approach is to match the ASUS part number, battery revision, voltage, physical shape and connector rather than selecting a battery purely because its model name appears similar.
8. Is this battery compatible with ASUS VivoBook X412F?
Yes. ASUS's own parts catalogue describes 0B200-03280700 as X412F BATT/COS POLY/C21N1818-2. If your X412F currently contains a C21N1818-2 or ASUS part 0B200-03280700, this is the correct replacement type.
9. Which ASUS X415 laptops are listed as compatible?
Current product compatibility information lists models including X415DA, X415EA, X415EP, X415FA, X415JA, X415JF, X415JP, X415KA, X415MA and X415UA. ASUS configurations can vary, so checking the battery originally fitted to your individual laptop is still recommended.
10. Which ASUS X515 laptops are listed as compatible?
Compatible models currently listed include X515DA, X515EA, X515EP, X515FA, X515JA, X515JF, X515JP, X515KA, X515MA and X515UA. Match your original battery label before installation because some laptop families can be produced with different battery revisions.
11. Is the C21N1818-2 compatible with ASUS P1412CEA or P1512CEA?
Yes. Current compatibility information for ASUS part 0B200-03280700 includes the P1412CEA and P1512CEA notebook models.
12. Will C21N1818-2 fit every ASUS X412, X415 or X515 laptop?
Do not assume so. ASUS laptop families can contain different internal configurations. The most reliable check is to match C21N1818-2 and/or 0B200-03280700 to the battery already fitted in your laptop and compare the physical shape and connector position.
13. C21N1818 vs C21N1818-1 vs C21N1818-2 – are they the same battery?
Do not treat them as automatically interchangeable. The suffix identifies a battery revision, and physical layout, capacity, connector arrangement or laptop compatibility can differ. If your original battery says C21N1818-2, replacing it with the same -2 revision or an ASUS-approved substitute part is the safest approach.
14. C21N1818-2 vs B21N1818 – what is the difference?
B21N1818-series batteries can have different capacities and revisions from C21N1818-2. Some owners have encountered lower-capacity B21N1818 replacements when they originally had a 37Wh C21N1818. Do not substitute one simply because the model numbers look similar unless exact compatibility is confirmed.
15. Can I replace my 37Wh C21N1818-2 with a 29Wh or 32Wh battery?
Only use a different-capacity pack when ASUS or the battery manufacturer specifically confirms compatibility with your exact laptop. A lower-capacity battery may provide shorter runtime, and a physically similar pack is not necessarily electrically or mechanically identical.
16. Can I replace this 7.7V battery with a 7.6V or 7.8V battery?
Do not choose a replacement based only on a small voltage difference. For the product on this page, the verified specification is 7.7V / 37Wh. Use the exact ASUS part number or an explicitly approved substitute to avoid compatibility problems.
17. How can I check whether this battery is correct before ordering?
Check four things: the battery model number, ASUS spare-part number, voltage and physical connector/shape. Ideally your original battery should show C21N1818-2 or a confirmed equivalent ASUS part number. Also check the exact laptop model printed on the underside of the notebook.
18. Where can I find the battery model number in my ASUS laptop?
Because this is an internal battery, the model number is normally printed on the battery label underneath the laptop's bottom cover. Look for text such as C21N1818-2, voltage, Wh capacity and ASUS or supplier part numbers.
19. Is the C21N1818-2 an internal or externally removable battery?
It is an internal battery. The laptop bottom cover must be removed to access it; it is not designed to slide out externally like older removable notebook batteries.
20. Is replacing a C21N1818-2 difficult?
The procedure is manageable for somebody experienced with laptop servicing, but the bottom cover and internal connectors are delicate. If you are not comfortable opening a notebook, disconnecting an internal battery and working around the motherboard, using a competent repair technician is safer.
21. How is the C21N1818-2 held inside compatible ASUS laptops?
ASUS repair documentation for compatible X415-family configurations shows the C21N1818-2 secured by three battery screws. The exact bottom-cover removal sequence and internal arrangement can differ between laptop models, so consult the service information for your exact notebook before starting.
22. Does a new C21N1818-2 need BIOS coding or battery pairing?
ASUS service documentation does not describe a separate battery-pairing or coding procedure for this pack. Once a correct battery is physically connected, the laptop should normally detect it automatically. If it is not recognised, check the connector and perform normal ASUS battery troubleshooting.
23. Why is my new ASUS battery not detected after installation?
First shut down the laptop and check that the battery connector is fully and evenly seated. Also verify the exact battery part number. If the connection is correct, reconnect the AC adapter, restart the laptop, install current ASUS/BIOS updates where appropriate and run MyASUS System Diagnosis. A hardware or motherboard charging fault can also cause a battery not to be detected.
24. Why does a newly installed battery stay at 0% and not charge?
Check the AC adapter first and confirm the battery is correctly connected. Allow a deeply discharged replacement some charging time while the laptop is off. If it remains at 0%, ASUS recommends battery/power troubleshooting and MyASUS diagnostics because the cause could be the battery, charger, connector or charging circuitry.
25. Why does my ASUS laptop stop charging at 60% or 80%?
This can be intentional. Compatible ASUS laptops may use Battery Health Charging / MyASUS Battery Care. Depending on the model, Maximum Lifespan mode can limit charging to around 60% and Balanced mode to around 80%. Select Full Capacity mode if you need charging to 100%.
26. Does stopping at 80% mean my replacement battery is faulty?
Not necessarily. If ASUS Battery Health Charging or Battery Care is enabled, an 80% charging limit can be normal behaviour. Check MyASUS or the Battery Health Charging utility before diagnosing the battery as defective.
27. Do I need to calibrate a new C21N1818-2 battery?
A modern lithium battery does not require old-style conditioning through repeated full discharges. If the Windows percentage or runtime estimate appears inaccurate after replacement, a normal charge/use cycle can help the system estimate remaining capacity, but repeatedly draining lithium batteries to 0% is not recommended as routine maintenance.
28. Should I fully charge the replacement battery before first use?
It is sensible to install the battery, connect the correct ASUS charger and allow it to charge normally before relying on maximum mobile runtime. New lithium batteries are commonly stored and transported at a partial state of charge rather than at 100%.
29. How long should a 37Wh C21N1818-2 last on one charge?
There is no single runtime figure. Battery life depends heavily on the processor, display brightness, Wi-Fi use, background applications, SSD activity, power profile and workload. A 37Wh battery will last much longer during light browsing than during gaming, video encoding or other high-power workloads.
30. Why is my battery runtime shorter than expected?
Check Windows power settings, screen brightness, processor usage, browser tabs, background applications and battery health. High CPU usage or a bright display can reduce runtime substantially even when the battery itself is healthy.
31. How can I check ASUS battery health in Windows?
Open Command Prompt and enter powercfg /batteryreport. Windows creates an HTML battery report containing information such as original design capacity, current full-charge capacity, charge history and cycle information where supported.
32. What should I compare in the Windows battery report?
The most useful comparison is Design Capacity vs Full Charge Capacity. Design Capacity represents the original intended capacity, while Full Charge Capacity estimates how much energy the battery can currently store. A significant reduction over time indicates normal battery wear.
33. How many charge cycles should an ASUS laptop battery last?
ASUS states that lithium-ion notebook batteries typically have a lifecycle of approximately 300–500 charge cycles, although battery degradation depends strongly on temperature, charging behaviour and workload.
34. How many years should a replacement laptop battery last?
There is no guaranteed number of years because lithium batteries age through both time and charge cycles. Heat, remaining at 100% for long periods and frequent deep discharges can accelerate capacity loss, while moderate temperatures and appropriate charging habits can extend useful life.
35. How can I extend the life of my C21N1818-2 battery?
Avoid excessive heat and unnecessary deep discharges. If your ASUS laptop supports Battery Health Charging, using its 60% or 80% charging limit can be useful when the notebook spends most of its time connected to mains power.
36. Is it OK to leave my ASUS laptop plugged in all day?
Modern ASUS laptops manage charging electronically, but keeping a lithium battery continuously near 100% at elevated temperatures can accelerate long-term aging. When supported, ASUS Battery Health Charging/Battery Care can limit the maximum charge level for systems that spend most of their time plugged in.
37. How should I store the laptop if I will not use it for several months?
ASUS recommends storing a device at approximately 50% battery charge, powered off and disconnected from the AC adapter. For extended storage, periodically recharge it to around 50% to avoid excessive self-discharge.
38. What should I do if my ASUS battery is swollen?
Stop using a swollen battery and replace it. Do not press, bend, puncture or attempt to flatten the battery. A swollen pack should also be disposed of through an appropriate battery recycling or electronic-waste facility rather than normal household rubbish.
39. Can a swollen battery damage the laptop?
Yes. Physical expansion can put pressure on the bottom cover, keyboard, touchpad and internal components. If the case begins separating, the touchpad rises or the chassis becomes distorted, inspect the battery promptly rather than forcing the laptop casing back together.
40. How should the old C21N1818-2 battery be disposed of?
Lithium laptop batteries should be taken to an approved battery recycling or electrical-waste collection point. Do not place a lithium battery—particularly a damaged or swollen one—in normal household waste.
41. Do I need a new charger when replacing the battery?
Normally no. If your existing genuine/compatible ASUS AC adapter is functioning correctly and is the correct specification for the laptop, replacing the battery does not require replacing the charger. A faulty charger can, however, imitate a battery-charging problem.
42. Can I use the laptop while the new battery is charging?
Yes. Normal laptop use while charging is supported. Heavy workloads may make charging slower because part of the charger's available power is being used by the processor, display and other components at the same time.
43. Why does Windows say “plugged in” but the battery is not charging?
First check whether ASUS Battery Health Charging is intentionally limiting the charge level. If not, verify the AC adapter, battery connection and Windows/ASUS diagnostics. ASUS also recommends current BIOS and system updates as part of battery-charging troubleshooting.
44. Why does my ASUS laptop switch off immediately when I unplug the charger?
This commonly indicates that the existing battery can no longer supply usable power, is disconnected or is not being recognised. A 2026 X412F owner described this exact replacement scenario. Confirm battery health and connections before assuming another motherboard fault.
45. Why does the battery percentage suddenly jump or drop?
Large percentage changes can occur when the battery's estimated state of charge is inaccurate or when an aging battery has significant capacity degradation. Generate a Windows battery report and compare Design Capacity with Full Charge Capacity to determine whether the battery has become heavily worn.
46. Why is Windows showing a strange runtime estimate after installing a new battery?
Windows calculates remaining time from recent power consumption. Immediately after replacement it may have limited usage history, so estimates can vary considerably. Normal use over subsequent charge cycles generally gives Windows more data for estimating runtime.
47. Do I need to update the BIOS after replacing the C21N1818-2?
A BIOS update is not normally required simply because the battery has been replaced. However, if charging or detection problems continue, ASUS includes BIOS/system updates among its troubleshooting recommendations. Always use the BIOS intended for your exact laptop model.
48. Will replacing the battery affect Windows or my files?
Replacing the internal battery does not normally erase Windows, applications or files because those are stored on the laptop's SSD or hard drive. As with any internal repair, shut the computer down correctly and back up important data before opening the laptop.
49. Does a new battery make the ASUS laptop faster?
Normally it does not directly increase CPU or SSD performance. Its main benefit is restoring portable runtime and reliable operation away from the charger. Some laptops may reduce performance when the battery or AC power system has a serious fault, but a replacement battery should not be purchased as a general performance upgrade.
50. What warranty does this ASUS battery have from Memox?
The current Memox product specification lists a 3-month warranty for ASUS part 0B200-03280700. Warranty terms do not replace your applicable UK statutory consumer rights.
51. Genuine ASUS C21N1818-2 vs third-party replacement – which should I choose?
A genuine ASUS battery offers the advantage of an ASUS-specified part number, known physical fit, correct connector and original electrical specification. Third-party batteries can vary considerably in cell quality, capacity accuracy, protection circuitry and revision compatibility, so price alone should not determine the choice.
52. Why is matching 0B200-03280700 better than searching only for “ASUS X412F battery”?
Laptop model families can be produced in many hardware configurations. Searching by the exact ASUS spare-part number 0B200-03280700 and battery revision C21N1818-2 greatly reduces the risk of ordering a physically similar but incompatible battery.
53. Can I upgrade from 37Wh to a larger-capacity battery?
Only if ASUS explicitly provides a higher-capacity battery that is mechanically and electrically compatible with your exact notebook. Internal laptop batteries occupy precisely designed spaces, so a higher Wh rating alone does not mean a battery will physically fit or work correctly.
54. Who is this ASUS C21N1818-2 battery best for?
This battery is ideal for owners of a compatible ASUS X412F, selected X415/X515 or supported P-series notebook whose original 7.7V 37Wh C21N1818-2 battery has lost capacity, no longer holds charge, shuts down when unplugged or needs replacement due to age or swelling.
55. Who should NOT buy this C21N1818-2 battery?
Do not buy it simply because your laptop belongs to the wider ASUS VivoBook family. Choose another battery if your original pack has a different battery revision, different ASUS part number, different connector, different physical shape or an incompatible electrical specification. If you cannot identify your original battery, verify compatibility before ordering rather than guessing from the laptop's marketing name alone.
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