{"product_id":"lg-h791-replacement-battery-38v-2600mah-li-polymer","title":"LG BL-T19 H791 Replacement Battery 3.8V 2600mAh","description":"\u003cdiv class=\"bpw-desc\"\u003e\n  \u003ch2 class=\"bpw-desc-h2\"\u003eLG Nexus 5X \/ H791 — 3.8V Li-Polymer Replacement Battery (BL-T19)\u003c\/h2\u003e\n\n  \u003cp class=\"bpw-desc-lead\"\u003eThis is a 3.8V, 2600mAh Li-Polymer cell built to replace the BL-T19 in the LG Nexus 5X (H791, H791F, Bullhead). It fits the same physical cavity — 67.80 × 53.64 × 4.70 mm — and connects to the same charge IC the original cell used. If your Nexus 5X is shutting down unexpectedly or refusing to hold charge, the BL-T19 is the likely culprit.\u003c\/p\u003e\n\n  \u003cul class=\"bpw-desc-bullets\"\u003e\n    \u003cli\u003e\n\u003cstrong\u003eNexus 5X \/ Bullhead platform fit:\u003c\/strong\u003e\n    The H791, H791F, and Bullhead variants all run the same power rail and BMS handshake. They share the BL-T19 footprint and connector pinout, so one cell works across the full H791 lineup without modification.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eBench tested on actual hardware:\u003c\/strong\u003e\n    We cycled this cell through charge and discharge on an H791 unit. The BMS accepted the cell without flagging a protection fault, and the charge IC transitioned cleanly from constant-current to constant-voltage at 4.35V.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eFirst-cycle fast charge behaviour:\u003c\/strong\u003e\n    On first use after installation, disable fast charging for one complete discharge-charge cycle. This lets the fuel gauge IC recalibrate its coulomb counter against the new cell's discharge curve before high-current charging pushes into an uncalibrated state.\u003c\/li\u003e\n  \u003c\/ul\u003e\n\n  \u003chr class=\"bpw-desc-divider\"\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eWhy the Nexus 5X reports the wrong battery percentage after a cell swap\u003c\/h3\u003e\n\n  \u003cp class=\"bpw-desc-p\"\u003eThe Nexus 5X uses a coulomb-counter fuel gauge IC that tracks charge by measuring current in and out of the original cell. When you install a new cell, the IC still references the old discharge curve stored in its memory. The percentage display will drift — sometimes reading 80% when the actual state of charge is closer to 50%. One full discharge down to automatic shutdown, followed by an uninterrupted charge to 100%, forces the IC to remap its curve to the new cell. After that cycle, the percentage readout tracks accurately.\u003c\/p\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eSudden shutdown at 20–30% on the replacement cell\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eThis is a voltage-cliff issue, not a capacity problem. Under combined modem and screen load, the cell voltage can drop sharply at around 3.6V — faster than the fuel gauge IC anticipates — triggering an undervoltage shutdown even though the displayed percentage still looks safe. It almost always appears in the first few cycles before the IC has recalibrated. Run two full discharge-charge cycles without fast charging, and the shutdowns stop. If they continue past cycle three, check that cell voltage at shutdown is above 3.4V — below that points to a seating or connector issue rather than calibration.\u003c\/p\u003e\n\u003c\/div\u003e","brand":"BatteryWeb","offers":[{"title":"Warranty 1 Year","offer_id":43392110526554,"sku":"BWCS-LKH790SL-1","price":25.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 2 Year","offer_id":43392110559322,"sku":"BWCS-LKH790SL-2","price":28.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 3 Year","offer_id":43392110592090,"sku":"BWCS-LKH790SL-3","price":31.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0674\/4775\/0746\/files\/BW-CS-LKH790SL-1.webp?v=1779143847","url":"https:\/\/batteryweb.com\/products\/lg-h791-replacement-battery-38v-2600mah-li-polymer","provider":"BatteryWeb","version":"1.0","type":"link"}