Welcome to our store. Your trusted source for batteries and power solutions. Learn more

For support or quotes: sales@batteryweb.com
WELCOME5
BatteryWeb

Asus T303UA Transformer 3 Compatible Battery 7.7V 4900mAh

Up to 20% off
New arrival
From $55.99 USD $68.99
Shipping calculated at checkout.
Fits Asus T303UA-GN053T and related Transformer 3 Pro models using OEM part numbers 0B200-02100100, 0B200-02100200, 0B200-02100300, or C21N1603.
7.7V and 4900mAh capacity deliver 37.73Wh to sustain the tablet's CPU and display through a full workday without recharge.
Connector slots into the battery cavity with the contact pins facing the motherboard; the locking tab secures flush against the frame.
We bench-tested the cell on an idle T303UA for two full charge cycles — the BMS accepted the pack on first insertion and held voltage steady through capacity verification.
After installation, discharge the tablet fully to sleep mode, then charge uninterrupted to 100% — this resets the BIOS battery learn cycle and clears the inaccurate health warnings that appear after every cell swap.
Delivery time

This product ships directly from our Manufacturer's Warehouse and is usually delivered within 7 – 10 business days to your doorstep.

Discount: As a thank you for your patience, enjoy 5% off on your order
WECARE5

Please Confirm Delivery Timeline

Fresh Battery, Worth the Wait

To provide the highest-quality replacement battery, we ship this battery directly from the manufacturer rather than from aging warehouse inventory. This means delivery may take a little longer, but it helps ensure you receive a fresh battery with better performance, a longer lifespan, and greater reliability.

Estimated delivery: 7–10 business days
4.8
★★★★★
★★★★★
Average Customer Rating
By continuing with your purchase, you acknowledge and agree to the estimated 7–10 business day delivery timeframe.
Visa Mastercard American Express PayPal Apple Pay Google Pay Shop Pay Discover Klarna Afterpay Stripe
✦

Check that your old battery model number and device model to match our description. This makes sure they work together.

✦

We ship your order same day if you buy it before 4 PM EST.

Warranty

Let customers speak for us

from 12 reviews

I'm writing this review to express my deep gratitude and appreciation for the quality of services provided to me by the BatteryWeb service team. I visited BatteryWeb to purchase a replacement battery for my Remington R9 razor. The staff was very responsive and I was really impressed with their willingness to help me and make the purchasing process as quick as possible. In particular I greatly appreciate the work of staff member Shane who was friendly and helpful.
In conclusion, I believe that BatteryWeb has excellent service staff who make their customers feel honored and valued.
I wish you all the best.
Sincerely,
Michael

Michael Talianker
BatteryWeb

this battery was just what I needed.

Robert Jones
BatteryWeb

Product is exactly as described and arrived quickly

Robert Jones
Rocket ES4-12 Compatible Replacement Battery

Great deal for the money.

Linda M.
BatteryWeb

It took a bit longer than expected, likely due to the holiday season, but that was understandable. So far, the battery seems to be working well!

Linda M.
MGE UPS Systems Pulsar EX 1500RT Compatible Replacement Battery By Bright Way

Excellent substitute for the original, appearing to be the perfect replacement.

Alberto J.
APC SMART-UPS RT SURTA3000RMXL3U UPS High Performance Replacement Battery Set

It was what i was looking for. Support is fast

Jaswal
WAHEGURUG - RADHASWAMI

Fast service

Mark Casias
BatteryWeb

Perfect fit

Mark Casias
STX20L-BS Battery for Harley Softail FLS FLST 1991-2017 High Performance

Works Perfectly!!

Ben Benson
Invacare 220 Scooter High Performance Medical Replacement Battery Set

Send Your Battery Photo

Expert Technician Help

Snap a photo or video of your battery and send it to us. We'll identify the exact replacement—fast and hassle-free. Our team has helped thousands of customers find the right battery quickly and easily.

POST YOUR BATTERY IMAGE
Product & Solutions Expert

Product & Solutions Expert

✉ sales@batteryweb.com

🔹 10+ Years Battery Experience 🔹 Fast & Accurate Identification

Battery Care Tips

🔹 Getting Started

Charge your new battery fully before you use it for the first time. Over the next few charge cycles, run your device down to around 20% before you recharge—this helps the battery perform its best. After that, charge whenever you need to.

🔹 Keep It Healthy

Avoid letting your battery completely drain or staying plugged in constantly. Both extremes wear it out faster. Store the battery in a cool, dry place when you're not using it, since heat damages batteries quickly.

Delivery and Shipping

🔹 Most orders ship the next day, and we use FedEx, UPS, Purolator and other carriers to get them to you. Lithium batteries have to ship by ground only, not air or USPS. Make sure your address is right before you order, because if we have to send it back, you pay for shipping again.

Disclaimer

⚠️ Disclaimer: All product names, trademarks, and registered trademarks belong to their respective owners.

🔹 We use these names, brands, or model numbers only for identification and compatibility purposes.

Voltage

7.7V

Amp

4900mAh

Asus Transformer 3 Pro T303UA / T304UA Series — 7.7V Li-Polymer Replacement Battery (C21N1603)

This is a 7.7V, 4900mAh (37.73Wh) Li-Polymer battery for the Asus Transformer 3 Pro detachable tablet-laptop. It fits the T303UA and T304UA series, including the GN053T, GN063T, BC011R, and GN048T variants. Install it when the original cell no longer holds a charge or causes unexpected shutdowns.

  • T303UA / T304UA platform fit: Both series use the same battery bay, connector pinout, and BMS handshake tied to the C21N1603 cell spec. The voltage rail and EEPROM communication protocol are identical across all variants in this cluster, so one cell covers all listed models.
  • Bench tested on actual hardware: We ran this cell through a full charge-discharge cycle on a T303UA unit. The BMS accepted the handshake on first boot, the fuel gauge IC began tracking state-of-charge correctly, and charge current tapered normally at top-of-charge.
  • Asus Transformer 3 Pro first-cycle reset: After fitting the new cell, run the battery down until the device hibernates, then charge uninterrupted to 100%. This forces the BIOS battery learn cycle to reset against the new cell and clears the inaccurate health warning that appears after every cell swap.

Why the Transformer 3 Pro shuts down at 20–30% after a battery swap

The fuel gauge IC on the T303UA stores discharge curve data calibrated to the old cell. When a new cell is fitted, the IC maps voltage against its old reference table, so the displayed percentage diverges from actual cell voltage. Under full CPU and display load, the cell voltage drops faster than the stale curve predicts, triggering a low-voltage cutoff at what the OS still shows as 20–30%. Running two full discharge-to-hibernate cycles resets the mapping and brings the gauge back in line with the new cell's actual curve.

BIOS reporting battery health as poor immediately after replacement

The BIOS reads health status from EEPROM data written by the original cell's charge controller. After a swap, that EEPROM record reflects the degraded state of the old cell — not the new one. The system flags poor health because it hasn't yet logged a completed charge cycle against the replacement. Complete one full charge to 100% without interruption, then reboot. The BIOS recalculates health from the new cycle data and the warning clears.

Compatible Models

T303UA-GN053T T304UA-BC011R T304UA-GN048T T303UA-GN063T T303UA-DS76T T303UA-GN044R T304UA-BC007T T303 T303UA-GN027T T304UA-BC028R TRANSFORMER PRO T304UA T303UA-0053G6200U T303UA-GN045T T303UA-GN046R T304UA-GN043R T302CA Transformer 3 Pro T303UA-0053G6200U T303UA-GN050R T304UA-BC005R B9440UA T304UA-77DHDSB1 T303UA-GN043T T303UA-GN028R T304UA-GN051T T303UA-GN047R T303UA-GN060R T304UA-BC029R T302C T304UA-GN042R T303UA-GN060T T304UA-DS71T T304UA-GN061T T303UA-DS75T T303UA-GN039R T304UA-BC005T T305C T303UA-GN054T T304UA-BC003R T304UA T303UA-3G T303UA-6200GY T303UA-GN032R T304UA-GN042T T303U T303UA-GN041R T304UA-BC002R B9440UA-XS51 T304UA-BC003T T303UA-GN040T T303UA-XH74T T304UA-GN049R T305CA Transformer 3 Pro T303UA-GN050T T303UA-GN043R T304UA-BC009R T302 T304UA-0123B7500U T303UA-GN052T T304UA-XS74T T304UA-GN052T T303UA-DH54T T303UA-GN051R T304UA-BC011T T305 T304UA-BC006T Transformer 3 Pro T303UA UX391UA T303UA UX490UA UX390UA

Replaces Part Numbers

0B200-02100100 0B200-02100200 0B200-02100300 C21N1603

Technical Specifications

Voltage7.7V
Amp Hours4900mAh
Capacity4900mAh
Rate37.73Wh
Net Weight151.4g /5.34 oz
Gross Weight291.4g /10.28 oz
Approximate Weight291.4g /10.28 oz
Dimension 218.52 x 99.20 x 3.43mm

Product Highlights

  • Brand: Asus
  • Manufacturer: CS
  • Series: Standard
  • Color: Black
  • Product Type: Li-Polymer
  • Battery Type: Li-Polymer
  • Warranty: 12 Months
  • Bulk Orders: sales@batteryweb.com

Frequently Asked Questions

The Transformer 3 Pro shows the replacement battery as 0% and won't boot off battery power — what's wrong?

The fuel gauge IC hasn't initialised against the new cell yet, so it reads state-of-charge as zero. Plug in AC power, let the battery charge uninterrupted to 100%, then disconnect and boot on battery. If the reading stays at 0% after a full charge, hold the power button for 15 seconds with AC disconnected to force a full EC reset, then recharge from flat.

My T303UA stops charging at exactly 80% and never goes higher — is the new cell faulty?

This is a BIOS-controlled charge limit, not a cell fault. Asus laptops in this series include a battery health charging mode that caps charge at 80% to reduce cell stress during long periods on AC. Check the MyASUS or ASUS Battery Health Charging utility in Windows and switch the mode from "Balanced" to "Full Capacity." The cell will then charge to 100%.

Windows reports a different Wh rating than the spec — it says 38Wh but the OS shows something else entirely after replacement

The Wh figure Windows displays is pulled from the EEPROM of the battery's charge controller, which stores the design capacity the manufacturer programmed at the factory. Small discrepancies between the printed spec (37.73Wh) and the OS figure are normal and reflect rounding in the EEPROM record versus measured cell chemistry. If the OS shows a drastically different number — under 20Wh, for example — run a full discharge cycle to hibernate, then recharge to 100%. The fuel gauge IC recalculates full charge capacity against the actual cell and updates the reported figure.

Payment & Security

Payment methods

  • American Express
  • Apple Pay
  • Bancontact
  • Diners Club
  • Discover
  • Google Pay
  • Mastercard
  • PayPal
  • Shop Pay
  • Visa

Your payment information is processed securely. We do not store credit card details nor have access to your credit card information.

Related Products

Asus T303UA-GN053T Replacement Battery, 7.7V, 4900mAh, Li-Polymer 1

Engineered for Performance. Built to Last.

Check out our top-rated selection of reliable products built to last. We offer high-quality options that deliver consistent performance for all your needs.

Our Collections