{"product_id":"fujitsu-lifebook-t4210-replacement-battery-108v-4600mah-li-ion","title":"Fujitsu FPCBP155 LifeBook T4210 Replacement Battery 10.8V 4600mAh","description":"\u003cdiv class=\"bpw-desc\"\u003e\n  \u003ch2 class=\"bpw-desc-h2\"\u003eFujitsu LifeBook T4210 Series — 10.8V Li-ion Replacement Battery (FPCBP155)\u003c\/h2\u003e\n\n  \u003cp class=\"bpw-desc-lead\"\u003eThis is a 10.8V 4600mAh Li-ion battery for the Fujitsu LifeBook T4210, T4215, and T4220 Tablet PC. These are convertible tablet-notebook hybrids from the mid-2000s that depend on a working battery for any unplugged operation. This cell replaces OEM part numbers FPCBP155, FPCBP155AP, and S26391-F405-L600.\u003c\/p\u003e\n\n  \u003cul class=\"bpw-desc-bullets\"\u003e\n    \u003cli\u003e\n\u003cstrong\u003eT4210, T4215, and T4220 compatibility:\u003c\/strong\u003e\n    All three models share the same 10.8V battery rail, connector pinout, and BMS communication protocol — one cell fits all three without modification.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eBench tested on actual hardware:\u003c\/strong\u003e\n    We ran this cell through charge and discharge cycles on the T4210 platform. The BMS handshook correctly, charge termination triggered at 100%, and the protection circuit responded to over-current conditions as expected.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003ePost-install calibration on the T4210:\u003c\/strong\u003e\n    After fitting this cell, run the laptop down to hibernate-cutoff under normal use, then charge it uninterrupted to 100%. This resets the BIOS battery learn cycle and clears the inaccurate health warning that appears after every cell swap on this platform.\u003c\/li\u003e\n  \u003c\/ul\u003e\n\n  \u003chr class=\"bpw-desc-divider\"\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eBIOS reporting poor battery health after swapping the cell on the T4210\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eThe T4210 BIOS reads health data stored in the battery's EEPROM, not from live cell measurements. When a new cell arrives, that EEPROM data does not match the old unit's learned values, so the system flags the battery as degraded. This is a data mismatch, not a fault with the cell itself. Running one full discharge-to-hibernate then a complete uninterrupted charge lets the BIOS rewrite its learned capacity values and clear the warning.\u003c\/p\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eFuel gauge jumping erratically for the first few cycles after replacement\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eThe fuel gauge IC on the T4210 estimates remaining capacity based on charge and discharge curves it learned from the previous cell. A new cell has different internal resistance and a slightly different voltage curve, so the gauge reads wildly off until it recalibrates. Expect inaccurate percentage readings for the first two to three full cycles — this is normal IC behaviour, not a battery defect. After two or three full discharge and charge cycles, the gauge IC locks onto the new cell's curve and the readout stabilises.\u003c\/p\u003e\n\u003c\/div\u003e","brand":"BatteryWeb","offers":[{"title":"Warranty 1 Year","offer_id":43410844024922,"sku":"BWCS-FU4210NB-1","price":86.99,"currency_code":"USD","in_stock":false},{"title":"Warranty 2 Year","offer_id":43410844057690,"sku":"BWCS-FU4210NB-2","price":102.99,"currency_code":"USD","in_stock":false},{"title":"Warranty 3 Year","offer_id":43410844090458,"sku":"BWCS-FU4210NB-3","price":113.99,"currency_code":"USD","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0674\/4775\/0746\/files\/BW-CS-FU4210NB-big.webp?v=1779581320","url":"https:\/\/batteryweb.com\/products\/fujitsu-lifebook-t4210-replacement-battery-108v-4600mah-li-ion","provider":"BatteryWeb","version":"1.0","type":"link"}