{"product_id":"lenovo-ideapad-l340-15irh-replacement-battery-114v-3900mah-li-polymer","title":"Lenovo IdeaPad L340-15IRH Replacement Battery 11.4V 3900mAh","description":"\u003cdiv class=\"bpw-desc\"\u003e\n  \u003ch2 class=\"bpw-desc-h2\"\u003eLenovo IdeaPad L340-15IRH \/ L340-17IRH — 11.4V Li-Polymer Replacement Battery (5B10T04975)\u003c\/h2\u003e\n\n  \u003cp class=\"bpw-desc-lead\"\u003eThis is an 11.4V, 3900mAh (44.46Wh) Li-Polymer battery for the Lenovo IdeaPad L340-15IRH, L340-17IRH, and L340 SP\/B series notebooks. It replaces the original cell when charge capacity has dropped or the battery no longer holds voltage under load. OEM part numbers covered: 5B10T04975, 5B10W67350, L18M3PF1, and SB10W67407.\u003c\/p\u003e\n\n  \u003cul class=\"bpw-desc-bullets\"\u003e\n    \u003cli\u003e\n\u003cstrong\u003eL340-15IRH and L340-17IRH compatibility:\u003c\/strong\u003e\n    Both models share the same 11.4V three-cell architecture, connector pinout, and BMS handshake protocol. The L340 SP\/B variant uses the same board layout, so 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 L340-series hardware. The BMS negotiated correctly with the Lenovo EC firmware, held stable voltage across CPU and display load spikes, and reported capacity accurately after two calibration cycles.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eFirst-cycle reset after install:\u003c\/strong\u003e\n    After fitting this battery, run one full discharge to hibernate-cutoff, then charge uninterrupted to 100%. This forces the BIOS battery learn cycle to reset against the new cell and clears the inaccurate health warning that appears on the first boot after every cell swap.\u003c\/li\u003e\n  \u003c\/ul\u003e\n\n  \u003chr class=\"bpw-desc-divider\"\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eWhy the L340 shuts down at 20–30% after a battery swap\u003c\/h3\u003e\n\n  \u003cp class=\"bpw-desc-p\"\u003eThe L340's fuel gauge IC retains calibration data from the old cell. When a new cell is installed, the IC maps voltage curves from the previous battery onto different chemistry characteristics. Under combined CPU and display load, the new cell hits a voltage cliff the IC wasn't expecting, and the EC interprets this as a critically low state-of-charge. Running two full discharge-to-hibernate and charge-to-100% cycles re-trains the fuel gauge IC against the actual voltage profile of the replacement cell. After those cycles, the reported percentage and the physical cutoff voltage align correctly.\u003c\/p\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eBIOS showing battery health as \"Poor\" or \"Replace Now\" on a brand-new cell\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eLenovo's BIOS reads health status from EEPROM data embedded in the battery's BMS board. On a new replacement cell, the EEPROM cycle count is zero and the rated Wh value may differ slightly from the original OEM figure, which some BIOS versions flag as a mismatch. This is a firmware interpretation issue, not a fault with the cell. Run the Lenovo Vantage battery gauge reset or perform one complete discharge-to-hibernate followed by a full uninterrupted charge — the BIOS health indicator typically clears to \"Normal\" once the learn cycle completes and the EC logs at least one full charge event.\u003c\/p\u003e\n\u003c\/div\u003e","brand":"BatteryWeb","offers":[{"title":"Warranty 1 Year","offer_id":43409650352218,"sku":"BWCS-LVL340NB-1","price":97.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 2 Year","offer_id":43409650384986,"sku":"BWCS-LVL340NB-2","price":111.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 3 Year","offer_id":43409650417754,"sku":"BWCS-LVL340NB-3","price":122.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0674\/4775\/0746\/files\/BW-CS-LVL340NB-1.webp?v=1779580311","url":"https:\/\/batteryweb.com\/products\/lenovo-ideapad-l340-15irh-replacement-battery-114v-3900mah-li-polymer","provider":"BatteryWeb","version":"1.0","type":"link"}