Product Overview
The C31N1821 is a premium OEM-grade replacement battery built for the ASUS ZenBook S13 UX392 series ultrabook, restoring a dependable 50Wh (4335mAh) of power at 11.55V so you can keep working, streaming and creating all day without hunting for a power outlet. Engineered as a direct drop-in match for the original ASUS battery, it ends random shutdowns, rapid drain and charging failures.
Each battery is assembled from high-quality Li-ion cells with an intelligent Battery Management System (BMS) for overcharge, over-discharge, over-current and short-circuit protection, passes strict pre-shipment quality checks, and is backed by a 1-year warranty. Please note: this C31N1821 interface is on the right, not on the left - please confirm this detail clearly when placing your order.
Specifications
| Standard Model | C31N1821 |
| Battery Type | Li-ion |
| Voltage | 11.55V |
| Capacity | 50Wh / 4335mAh |
| Color | Black |
| Condition | Replacement Battery (100% Brand New, 1-year warranty!) |
| Warranty | 1-Year Warranty |
Replace Part Numbers
- C31N1821
- 0B200-03210100
Compatible Models
Fits the following ASUS ZenBook S13 models (always confirm the battery model printed on your original battery before ordering):
- For ASUS ZenBook S13 UX392 Series
- For ASUS ZenBook UX392F
- For ASUS ZenBook S13 UX392FA-AB004T
- For ASUS ZenBook S13 UX392FA-AB017T
- For ASUS ZenBook S13 UX392FN-XS71
- For ASUS ZenBook S13 UX392FN-0042B8265U
FAQ
Will the C31N1821 battery fit my ASUS ZenBook S13 laptop?
This C31N1821 battery fits the ASUS ZenBook S13 UX392 series, including UX392F, UX392FA and UX392FN models such as UX392FA-AB004T, UX392FA-AB017T, UX392FN-XS71 and UX392FN-0042B8265U. Before ordering, please confirm the model printed on your original battery label matches C31N1821.
What capacity and voltage does this battery provide?
The battery delivers 50Wh / 4335mAh at 11.55V, matching the original OEM specification (replacing part number 0B200-03210100) to restore the full runtime your ZenBook S13 had when new.
Which side is the connector on for this C31N1821 battery?
Please note: this C31N1821 interface is on the right, not on the left. Please confirm this detail clearly when placing your order so you receive the correct orientation.
Is the battery safe and covered by a warranty?
Yes. It is 100% brand new with a built-in BMS providing overcharge, over-discharge, over-current and short-circuit protection, is CE-compliant, and is covered by a 1-year warranty with reliable after-sales support.
Note:
This is not a complete list or inclusion of all compatible laptop models. You can open the back of your laptop to check the original battery model. If you have any compatibility questions, please contact us online.The casing is made of durable materials, the mainboard adopts advanced technology, and the battery core is produced with high-quality raw materials to ensure that it will not be damaged after long-term use.
Our products are equipped with multiple protection technologies such as overvoltage, overcurrent, and overcharge to effectively protect the safety of batteries and equipment.
China warehouse delivery method
Overseas Warehouse Shipping Times & Costs
Payment Methods
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Account Name: ShenZhen KingSener Science and Technology Co., Ltd
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Bank Transfer
Q&A
Quick FAQ:Laptop Battery Care & Troubleshooting
- What Should I Know Before Buying a Laptop Battery Replacement?A: Before buying a laptop battery replacement, confirm your laptop’s exact model number and the part number printed on the original battery. Check the battery voltage, connector, physical dimensions, and compatibility list. Do not choose a battery based on appearance alone, because similar laptop models may use different batteries. Review the seller’s warranty, return policy, and product specifications before ordering.
- How Do I Find a Compatible Laptop Battery for My Device?A: To find a compatible laptop battery, identify your laptop’s full model number and the part number on the original battery. Compare these details with the replacement battery’s compatibility list and specifications, including voltage, connector type, and dimensions. If you are unsure, contact customer support with your laptop model and original battery part number before placing an order.
- Can I leave my laptop plugged in 24/7?Yes, the built-in TI chip prevents overcharging. Tip: To prevent long-term cell swelling, unplug and drain the battery to 40% twice a month.
- Why Is My Laptop Battery Not Charging?A: A laptop battery may not charge because of a faulty AC adapter, damaged charging port, loose connection, temperature protection, battery-health settings, or a worn-out battery. Confirm that you are using a compatible charger and inspect the cable and port for visible damage. Restart the laptop and review the manufacturer’s battery or charging settings. If the battery becomes unusually hot, swollen, or damaged, stop using it and seek professional assistance.
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Are BatteryMall Laptop Batteries Reliable?BatteryMall laptop batteries are designed with safety and reliability in mind. All batteries feature built-in IC protection against short-circuits, over-voltage, and overheating, helping protect the battery during normal use. They are also CE, FCC, and RoHS certified. For the best experience, choose a compatible laptop battery that matches your exact laptop model and original battery part number, and follow the installation and care instructions. BatteryMall also provides a 1-year warranty on KingSener batteries purchased from BatteryMall; see the Product Warranty page for details.