Toshiba Tecra A3X-165 Compatible Battery 10.8V 4400mAh
This product ships directly from our Manufacturer’s Warehouse and is usually delivered within 5 – 8 business days to your doorstep.
WECARE5
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.
Toshiba Tecra A3X-165 Compatible Battery 10.8V 4400mAh - is backordered and will ship as soon as it is back in stock.
Let customers speak for us
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
✉ sales@batteryweb.com
Battery Care Tips
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
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
⚠️ 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.
Toshiba Tecra A3X-165 Compatible Battery 10.8V 4400mAh - is backordered and will ship as soon as it is back in stock.
Voltage
10.8V
Amp
4400mAh
Toshiba Tecra A3X-165 / M9 Series — 10.8V Li-ion Replacement Battery (PA3356U-1BRS)
This is a 10.8V, 4400mAh (47.52Wh) Li-ion replacement battery for the Toshiba Tecra A3X-165 and Tecra M9 series business notebooks. It also fits the Dynabook Qosmio F20 and over 170 additional Toshiba models sharing the same connector and voltage rail. OEM cross-references include PA3356U-1BRS, PABAS071, PABAS048, and PA3588U-1BRS among others.
- Tecra A3X and M9 platform compatibility: These models share a common 10.8V three-cell Li-ion architecture, identical connector pinout, and the same BMS handshake protocol — which is why a single cell works across the full Tecra A3 and M9 range without firmware modification.
- Bench tested on actual hardware: We ran this cell on a Tecra M9 chassis and confirmed the BMS negotiated charge cycles correctly, accepted a full charge to 47.52Wh, and passed voltage-under-load checks at both idle and peak CPU draw without triggering a cutoff.
- First-cycle calibration on Tecra models: After installing, run one full discharge until the laptop hibernates at cutoff, then charge uninterrupted to 100%. This resets the BIOS battery learn cycle and clears the inaccurate health or "unknown battery" warning that commonly appears after every cell swap on this platform.
BIOS reporting poor battery health immediately after fitting a new cell
The Tecra BIOS reads health data stored in the battery's EEPROM and compares it against its internal baseline from the previous cell. A brand-new cell carries factory EEPROM values that don't match the BIOS's learned profile, triggering a false "degraded" or "poor health" flag. This is not a fault with the replacement cell. Run a single full discharge-to-hibernate followed by an uninterrupted charge to 100% — the BIOS resets its learn cycle and the warning clears.
Tecra A3X shutting down at 20–30% charge shown on screen
This happens when the fuel gauge IC has not yet calibrated against the new cell's actual discharge curve. The OS reads a percentage based on the old cell's profile, but the new cell hits its lower voltage cliff at a different point — the laptop cuts power before the gauge reaches zero. It looks like a faulty battery but is a calibration mismatch. Complete two full discharge-to-hibernate and full-charge cycles; the fuel gauge IC recalibrates and shutdowns stop occurring above approximately 10.8V cutoff.
Compatible Models
Replaces Part Numbers
Technical Specifications
Product Highlights
- Brand: Toshiba
- Manufacturer: CS
- Series: Standard
- Color: Black
- Product Type: Li-ion
- Battery Type: Li-ion
- Warranty: 12 Months
- Bulk Orders: sales@batteryweb.com
Frequently Asked Questions
My Toshiba Tecra shows the battery Wh rating as wrong in system information after swapping to this cell — is the battery defective?
No. The Wh figure displayed in Windows or Toshiba Power Saver pulls from EEPROM data embedded in the cell, which reflects the rated chemistry value rather than the actual measured capacity of the new cell. The two numbers can differ by a few watt-hours without any fault present. Run a full discharge-to-hibernate cycle followed by a complete charge, and the reported figure will update to reflect the cell's actual capacity.
The replacement battery charges normally but the fuel gauge jumps around wildly for the first few days — what's causing that?
The fuel gauge IC inside the Tecra needs several charge and discharge cycles to map its algorithm against the new cell's specific discharge curve. Until it has that data, the percentage readout interpolates from the old cell's profile and produces erratic jumps. This is not a battery fault. Run two or three full discharge-to-hibernate and full-charge cycles back-to-back and the gauge stabilises.
My Tecra A3X won't charge the new battery above 80% — is there a fix?
The Toshiba BIOS on several A3X and M9 models includes a charge limit setting that caps charging at 80% to reduce cell wear during extended AC use. Check Toshiba Power Saver or HWSetup utility under the battery tab — a "battery care mode" or "eco charge" toggle will be enabled. Disable it, unplug and reconnect the AC adapter, and the battery will charge to 100%.
Payment & Security
Payment methods
Your payment information is processed securely. We do not store credit card details nor have access to your credit card information.
Related Products
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.





