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

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

Toshiba Tecra M7 10.8V Replacement Battery PA3128U-1BRS

Up to 20% off
New arrival
From $69.99 USD $86.99
Shipping calculated at checkout.
Fits Toshiba Tecra M7-ST4013 and replaces OEM part numbers PA3128U-1BRS, PA3191U-1BRS, PA3191U-2BRS, PA3191U-3BRS, PA3191U-4BRS, and PA3191U-5BRS.
This 10.8V 4400mAh cell restores full charge capacity to mid-2000s Tecra business notebooks after degradation.
Connector slides straight into the battery bay with a single locking tab that seats flush against the chassis.
We ran a full discharge cycle on a Tecra M7 and confirmed the BMS voltage held steady through cutoff with no early shutdown.
After installation, discharge fully to hibernate then charge uninterrupted to 100% — this resets the BIOS battery learn cycle and clears false health warnings.
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 11 reviews

Product is exactly as described and arrived quickly

Robert Jones
Rocket ES4-12 Compatible Replacement Battery

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

10.8V

Amp

4400mAh

Toshiba Tecra M7 / Portégé M700 Series — 10.8V Li-ion Replacement Battery (PA3128U-1BRS)

This 10.8V, 4400mAh (47.52Wh) Li-ion battery replaces the original cell in the Toshiba Tecra M7-ST4013, Portégé M700-S7004X Tablet PC, Portégé M405, Portégé M205-S809, and over 125 additional Toshiba Tecra and Portégé models. It cross-references OEM part numbers PA3128U-1BRS, PA3191U-1BRS, PA3191U-2BRS, PA3191U-3BRS, PA3191U-4BRS, PA3191U-5BRS, and the BAS suffix variants. Voltage, pin layout, and BMS handshake match the original spec.

  • Tecra M7 and Portégé M700 platform fit: These models share the same 10.8V three-cell-series architecture, a common 9-pin SMBus connector, and the same BMS communication protocol. One cell part number covers the full group without any hardware modification.
  • Bench tested on actual hardware: We ran this cell through charge and discharge cycles on a Tecra M7 unit. The BMS reported state-of-charge correctly, charge termination triggered at the expected voltage ceiling, and no fault codes appeared in the SMBus log.
  • First-cycle calibration on the Tecra M7: After installing, run the laptop on battery alone until it hibernates from low charge, then charge uninterrupted to 100% without waking the system. This resets the BIOS battery learn cycle and clears the inaccurate health warning that appears after every cell swap on this platform.

BIOS reporting poor battery health immediately after fitting a new cell

The Tecra M7 BIOS reads health data from the battery's EEPROM, not from a live capacity measurement. When a new cell arrives, that EEPROM contains factory default values that don't match the BIOS's learned data from the old cell. The system flags this mismatch as degraded health before the new cell has run a single cycle. One full discharge-to-hibernate followed by an uninterrupted charge to 100% forces the BIOS to rewrite its learned values against the new cell's actual EEPROM data and clears the warning.

Laptop shuts down abruptly at 20–30% charge shown on screen

This is a voltage cliff symptom, not a firmware bug. Under full CPU and display load, the cell voltage drops faster than the fuel gauge IC can update its state-of-charge estimate, so the BIOS sees a critical undervoltage condition before the percentage readout reaches zero. It triggers an immediate shutdown to protect the cell. Run two complete calibration cycles — full discharge to hibernate cutoff, then full charge to 100% — to synchronise the fuel gauge IC with the new cell's actual discharge curve. After calibration, the shutdown threshold should move to below 5% at the same load.

Compatible Models

Tecra M7-ST4013 Portege M700-S7004X Tablet PC Portege M405 Portege M205-S809 Portege M400 Tablet PC Portege M700-S7008X Tablet PC Portege M200-122 Portege M700-S7001X Tablet PC Portege M400-S5032 Tablet PC Portege M750-S7212 Portege M400-S4034 Portege M700-13P Tecra M4-S435 Tecra M7-118 Portege M750-10J Satellite Pro 6100 Satellite Pro 6050 Portege M750-S720 Portege M200 Portege M400-S4031 Tablet PC Portege M700-S7044V Tablet PC Satellite R25 Portege M700-S7004V Tablet PC Tecra M7-S7331 Portege M700-S7043X Tablet PC Portege M700-S7003X Tablet PC Portege M400-S933 Tablet PC Portege M200-S838 Tecra M4-103 Portege M700-S7008 Tablet PC Portege M200-102 Portege M700 Series Tablet PC Portege M400-EZ5031 Tablet PC Portege M700-139 Portege M400-ST4035 Portege M750-10L Tecra M4 Tecra M4-107 Portege M750-109 Satellite Pro 6000 Satellite R10-101 Tablet PC Portege M750-S7201 Tecra M7 Portege M700-S7043V Tablet PC Satellite R20-ST4113 Portege M700-S7003V Tablet PC Tecra M7-S7311 Portege M700-S7005X Tablet PC Portege M405-S8003 Portege M205-S810 Portege M400-ST9113 Tablet PC Portege M200-S218TD Portege M200-152 Portege M700-S7002 Tablet PC Satellite R10 Portege M400-S5032X Tablet PC Portege M750-S7213 Portege M400-ST4001 Tablet PC Portege M700-13A Tecra M4-S115TD Satellite R25-S3513 Portege M750-10K Tecra TE2000 Satellite R15 Portege M750-ST7258 Portege M205 Portege M400-S4032 Tablet PC Tecra TE2100 Satellite R25-S3503 Portege M700-S7005V Tablet PC Satellite R20 Portege M700-S7044X Tablet PC Portege 4000 Portege M400-EZ5031 Portege M400-S4031 Portege M400-S4032 Portege M400-S4033 Portege M400-S4035 Portege M400-S5032 Portege M400-S5032X Portege M400-S933 Portege M400-ST4001 Portege M400-ST9113 Portege M700 Tablet PC Portege M700-S7001X Portege M700-S7002 Portege M700-S7003V Portege M700-S7003X Portege M700-S7004V Portege M700-S7004X Portege M700-S7005V Portege M700-S7005X Portege M700-S7008 Portege M700-S7008X Portege M700-S7043V Portege M700-S7043X Portege M700-S7044V Portege M700-S7044X Portege M750-S7202 Portege M750-S7211 Portege M750-S7221 Portege M750-S7222 Portege M750-S7223 Portege M750-S7241 Portege M750-S7242 Portege M750-S7243 PORTEGE M780-S7210 Portege M780-S7214 Portege M780-S7220 Portege M780-S7224 Portege M780-S7230 Portege M780-S7234 Portege M780-S7240 Portege M780-S7244 Portege M780-ST7200 Portege M780-ST7201 Portege M780-ST7202 Satellite Pro 6100 Series Satellite R10-S802TD Satellite R10-S820 Satellite R15-S822 Satellite R15-S8222 Satellite R15-S829 Satellite R20-ST2081 Satellite R25 Series Tecra M4-S315 Tecra M4-S335 Tecra M4-S415 Tecra TE 2100

Replaces Part Numbers

PA3128U-1BRS PA3191-2BAS PA3191U-1BAS PA3191U-1BRS PA3191U-2BRS PA3191U-3BAS PA3191U-3BRS PA3191U-4BAS PA3191U-4BRS PA3191U-5BRS

Technical Specifications

Voltage10.8V
Amp Hours4400mAh
Capacity4400mAh
Rate47.52Wh
Net Weight307g /10.83 oz
Gross Weight457g /16.12 oz
Approximate Weight457g /16.12 oz
Dimension 126.45 x 69.67 x 20.20mm

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 Tecra M7 shows the new battery as "0% available (plugged in, charging)" and never updates — what's happening?

The fuel gauge IC on the Tecra M7 motherboard holds calibration data from the old cell in its internal registers. When a new cell with different EEPROM values is installed, the IC loses its reference points and reports 0% or a frozen percentage until it runs a full learn cycle. Discharge the laptop completely on battery until it hibernates, then charge uninterrupted to 100% twice. After those two cycles the fuel gauge IC recalibrates against the new cell and the percentage readout tracks correctly.

Windows reports the new battery's capacity as 38Wh, but the product spec says 47.52Wh — is something wrong with the cell?

Nothing is wrong. The Wh figure Windows shows is pulled from the battery EEPROM's "design capacity" field, which is written at the factory in mWh units and can differ from the rated label spec by 5–10% depending on the cell batch. The 47.52Wh figure in the product data is the rated nameplate value. Run a full discharge and full charge cycle — the BIOS battery learn cycle updates the reported value closer to the actual measured capacity and the discrepancy typically drops below 2Wh.

The replacement battery charges normally but the Toshiba Power Saver utility keeps showing a red battery icon and "battery performance is low" — how do I clear it?

The Toshiba Power Saver utility reads its health assessment from the BIOS battery learn data, not directly from the cell. A freshly installed cell has no learned data stored, so the utility defaults to a degraded status flag. Open Toshiba Power Saver, go to Battery section, and run the Battery Recalibration function — this forces a controlled discharge to the BIOS cutoff voltage and a full recharge, after which the utility reads the new cell's actual capacity data and clears the red icon.

Payment & Security

Payment methods

  • American Express
  • Apple Pay
  • 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

Toshiba Tecra M7-ST4013 Replacement Battery, 10.8V, 4400mAh, Li-ion 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