{"product_id":"htc-e1-replacement-battery-37v-2100mah-li-ion","title":"HTC One E1 BM65100 Replacement Battery 3.7V 2100mAh","description":"\u003cdiv class=\"bpw-desc\"\u003e\n  \u003ch2 class=\"bpw-desc-h2\"\u003eHTC One E1 \/ 603e Series — 3.7V Li-ion Replacement Battery (BM65100)\u003c\/h2\u003e\n\n  \u003cp class=\"bpw-desc-lead\"\u003eThis is a 3.7V, 2100mAh Li-ion replacement cell for the HTC One E1, 603e, and related CSN\/HTX21UAA variants. It slots into any device originally fitted with OEM part BM65100, 35H00215-00M, or BA S930. Swap it in when your original cell no longer holds a charge or causes unexpected shutdowns.\u003c\/p\u003e\n\n  \u003cul class=\"bpw-desc-bullets\"\u003e\n    \u003cli\u003e\n\u003cstrong\u003eE1 and 603e platform fit:\u003c\/strong\u003e\n    Both the E1 and 603e share the same 3.7V battery bay, connector pinout, and BMS handshake — that is why one cell covers this entire model group. The fuel gauge IC on both boards reads the same discharge curve from the BM65100 cell chemistry.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eBench tested on actual hardware:\u003c\/strong\u003e\n    We cycled this cell through a full charge-discharge sequence on an E1 unit. The BMS accepted the charge without throttling, temperature stayed within normal range, and the fuel gauge reached 100% without early cutoff.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eFuel gauge recalibration on first cycle:\u003c\/strong\u003e\n    On first use after installation, disable fast charging for one complete discharge-charge cycle. This lets the fuel gauge IC map its coulomb counter to the new cell's discharge curve before high-current charging begins pushing current into an uncalibrated cell.\u003c\/li\u003e\n  \u003c\/ul\u003e\n\n  \u003chr class=\"bpw-desc-divider\"\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\"\u003eThe E1's fuel gauge IC retains the discharge curve of the old, degraded cell after a swap. When the modem or display fires a high-current draw, the new cell's actual resting voltage briefly dips below the threshold the IC expects at that state of charge. The phone interprets this as a critical low-voltage event and shuts down — even though the cell still has capacity. One full discharge-to-zero followed by a slow charge corrects this by forcing the coulomb counter to reset against the new cell's true voltage floor.\u003c\/p\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003ePhone reports wrong battery percentage after cell swap\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eThe HTC One E1 uses a fuel gauge IC that learns the discharge curve of the cell it was calibrated against. A new cell has a different internal impedance profile, so the percentage reading drifts — often showing 100% too quickly or dropping sharply below 40%. This is not a faulty cell; it is the IC recalibrating. Run one full charge to 100%, then discharge the phone until it powers off on its own, then charge back to 100% without interruption. After that cycle, percentage reporting stabilises.\u003c\/p\u003e\n\u003c\/div\u003e","brand":"BatteryWeb","offers":[{"title":"Warranty 1 Year","offer_id":43404323356762,"sku":"BWCS-HTE100XL-1","price":31.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 2 Year","offer_id":43404323389530,"sku":"BWCS-HTE100XL-2","price":34.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 3 Year","offer_id":43404323422298,"sku":"BWCS-HTE100XL-3","price":38.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0674\/4775\/0746\/files\/BW-CS-HTE100XL-1.webp?v=1779369761","url":"https:\/\/batteryweb.com\/products\/htc-e1-replacement-battery-37v-2100mah-li-ion","provider":"BatteryWeb","version":"1.0","type":"link"}