{"product_id":"lenovo-tab-m8-replacement-battery-385v-4900mah-li-polymer","title":"L19D1P31 Lenovo Tab M8 Replacement Battery 3.85V 4900mAh","description":"\u003cdiv class=\"bpw-desc\"\u003e\n  \u003ch2 class=\"bpw-desc-h2\"\u003eLenovo Tab M8 TB8505F — 3.85V Li-Polymer Replacement Battery (L19D1P31)\u003c\/h2\u003e\n\n  \u003cp class=\"bpw-desc-lead\"\u003eThis 3.85V, 4900mAh lithium-polymer battery replaces part number L19D1P31 in the Lenovo Tab M8 (TB8505F). It fits directly into the tablet's battery bay and connects to the existing flex cable and charge IC. Capacity is 4900mAh (18.87Wh), matching the original cell specification.\u003c\/p\u003e\n\n  \u003cul class=\"bpw-desc-bullets\"\u003e\n    \u003cli\u003e\n\u003cstrong\u003eTab M8 TB8505F fitment:\u003c\/strong\u003e\n    The TB8505F uses a flat Li-Polymer cell at 3.85V nominal. The connector pinout and BMS handshake are specific to this board revision — swapping with a mismatched cell causes the charge IC to reject the battery or report erratic state-of-charge readings.\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 a TB8505F board. The BMS accepted the cell without error flags, charge IC communicated correctly, and state-of-charge reporting stabilised after one full calibration cycle.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eFuel gauge recalibration after swap:\u003c\/strong\u003e\n    After installation, run the tablet down to automatic shutoff, then charge uninterrupted to 100% without unplugging. This resets the fuel gauge IC calibration against the new cell's actual capacity curve and clears the inaccurate percentage readings that commonly appear after a battery swap.\u003c\/li\u003e\n  \u003c\/ul\u003e\n\n  \u003chr class=\"bpw-desc-divider\"\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eTab M8 shutting down between 15–25% remaining\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eThe TB8505F's shutdown threshold is triggered by voltage drop, not percentage. Under combined display and WiFi load, the cell voltage sags below the BMS cutoff before the fuel gauge reaches 0%. This is most common with a degraded original cell but can also appear after a swap if the fuel gauge IC hasn't been recalibrated to the new cell. Run one complete discharge-to-shutoff cycle followed by a full uninterrupted charge — this resets the low-voltage curve mapping and stops premature cutoff around the 3.5V mark.\u003c\/p\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eFast charging unavailable on the Tab M8 after battery replacement\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eThe Tab M8 uses USB-PD negotiation to enable higher charge rates. After a battery swap, the charge IC may default to standard 5V\/1A until it completes one accepted full charge cycle with the new cell. Plug into a USB-PD charger and allow the tablet to charge from below 10% to 100% without interruption. On the next charge session, the fast charge icon should reappear — if it doesn't, verify the charger outputs at least 5V\/2A and the cable is USB-PD rated.\u003c\/p\u003e\n\u003c\/div\u003e","brand":"BatteryWeb","offers":[{"title":"Warranty 1 Year","offer_id":43425833484378,"sku":"BWCS-LVM850SL-1","price":30.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 2 Year","offer_id":43425833517146,"sku":"BWCS-LVM850SL-2","price":34.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 3 Year","offer_id":43425833549914,"sku":"BWCS-LVM850SL-3","price":37.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0674\/4775\/0746\/files\/BW-CS-LVM850SL-1.webp?v=1779929903","url":"https:\/\/batteryweb.com\/products\/lenovo-tab-m8-replacement-battery-385v-4900mah-li-polymer","provider":"BatteryWeb","version":"1.0","type":"link"}