{"product_id":"lenovo-legion-y700-replacement-battery-387v-6400mah-li-polymer","title":"Lenovo Legion Y700 Replacement Battery L21C2P32 3.87V 6400mAh","description":"\u003cdiv class=\"bpw-desc\"\u003e\n  \u003ch2 class=\"bpw-desc-h2\"\u003eLenovo Legion Y700 \/ TB-9707F — 3.87V Li-Polymer Replacement Battery (L21C2P32)\u003c\/h2\u003e\n\n  \u003cp class=\"bpw-desc-lead\"\u003eThis is a 3.87V, 6400mAh Li-Polymer replacement battery for the Lenovo Legion Y700 gaming tablet (TB-9707F). It matches OEM part numbers L21C2P32, L21D2P32, L21L2P32, L21M2P32, and SB18D21931. Use this when the original cell no longer holds charge or the tablet shuts down under gaming load.\u003c\/p\u003e\n\n  \u003cul class=\"bpw-desc-bullets\"\u003e\n    \u003cli\u003e\n\u003cstrong\u003eLegion Y700 and TB-9707F compatibility:\u003c\/strong\u003e\n    Both model designations reference the same hardware generation. They share the same voltage rail, connector footprint, and BMS handshake protocol, so one cell revision covers both.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eBench tested on actual hardware:\u003c\/strong\u003e\n    We cycled this battery through charge and discharge on a TB-9707F board. The BMS accepted the cell without error flags, and the charge IC stepped through CC\/CV phases normally with no cutoff events.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eFuel gauge recalibration after swap:\u003c\/strong\u003e\n    After installation, run one full discharge to automatic shutoff, then charge uninterrupted to 100%. This resets the fuel gauge IC against the new cell and clears the inaccurate percentage readings that commonly appear after a battery replacement.\u003c\/li\u003e\n  \u003c\/ul\u003e\n\n  \u003chr class=\"bpw-desc-divider\"\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eLegion Y700 shutting down at 15–25% during gaming sessions\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eThe Legion Y700 pulls simultaneous load from the display, GPU, and WiFi radio during active gameplay. At around 3.5V cell voltage, this combined draw can trigger the BMS undervoltage cutoff before the OS registers 0%. The old degraded cell hits that voltage cliff earlier, which is why shutdowns happen at 15–25% rather than near empty. A new cell with full capacity pushes that cutoff point back toward true zero under the same load conditions.\u003c\/p\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eFast charging not available after battery replacement\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eThe Legion Y700 uses a proprietary fast charge protocol that the charge IC re-negotiates during the first accepted charge cycle on a new cell. If fast charging shows as unavailable after the swap, the controller has not yet completed that handshake. Plug into the original Lenovo charger — not a generic USB-C adapter — and let the battery charge fully without interruption. After one complete cycle to 100%, the fast charge option reappears in the battery settings.\u003c\/p\u003e\n\u003c\/div\u003e","brand":"BatteryWeb","offers":[{"title":"Warranty 1 Year","offer_id":43306859200602,"sku":"BWCS-LVY700SL-1","price":53.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 2 Year","offer_id":43306859233370,"sku":"BWCS-LVY700SL-2","price":63.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 3 Year","offer_id":43306859266138,"sku":"BWCS-LVY700SL-3","price":70.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0674\/4775\/0746\/files\/BW-CS-LVY700SL_1.webp?v=1777768791","url":"https:\/\/batteryweb.com\/products\/lenovo-legion-y700-replacement-battery-387v-6400mah-li-polymer","provider":"BatteryWeb","version":"1.0","type":"link"}