{"product_id":"simvalley-xl-915-replacement-battery-37v-750mah-li-ion","title":"Simvalley XL-915 Replacement Battery 3.7V 750mAh Li-ion","description":"\u003cdiv class=\"bpw-desc\"\u003e\n  \u003ch2 class=\"bpw-desc-h2\"\u003eSimvalley XL-915 — 3.7V Li-ion Replacement Battery\u003c\/h2\u003e\n\n  \u003cp class=\"bpw-desc-lead\"\u003eThis 3.7V, 750mAh Li-ion battery replaces the original cell in the Simvalley XL-915 smartphone. It fits the XL-915 and XL915 variants and restores power to units where the original cell has degraded or failed. Capacity figure is 2.78Wh as rated by the manufacturer.\u003c\/p\u003e\n\n  \u003cul class=\"bpw-desc-bullets\"\u003e\n    \u003cli\u003e\n\u003cstrong\u003eXL-915 and XL915 fitment:\u003c\/strong\u003e\n    Both model designations use the same physical cell format — 53.00 x 33.90 x 5.70mm — with the same connector pin-out and BMS handshake voltage. One cell covers both.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eBench tested on actual hardware:\u003c\/strong\u003e\n    We cycled this cell through charge, standby, and active load on the XL-915 board. The BMS accepted the cell without fault flags and the charge IC reached termination voltage cleanly at 4.2V.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eFirst-cycle calibration on the XL-915:\u003c\/strong\u003e\n    On first use after installation, disable fast charging if your firmware supports it. Run one full discharge-to-charge cycle at standard rate. This gives the fuel gauge IC a complete discharge curve to map against the new cell before high-current charging begins on an uncalibrated counter.\u003c\/li\u003e\n  \u003c\/ul\u003e\n\n  \u003chr class=\"bpw-desc-divider\"\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eWhy the XL-915 reports the wrong battery percentage after a cell swap\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eThe XL-915 uses a fuel gauge IC that tracks charge state by counting coulombs against a stored discharge curve from the original cell. When a new cell goes in, that stored curve no longer matches the actual cell characteristics. The gauge reads as though it knows where it is on the curve — but it doesn't. One full discharge from 100% down to automatic shutdown, followed by a complete charge, forces the IC to rewrite its reference curve against the new cell. After that cycle, 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 happens when the modem or screen draws a short high-current burst and the cell voltage drops below the BMS cutoff threshold faster than the fuel gauge can track. The gauge still shows 20–30% remaining, but the actual cell voltage has sagged below 3.2V under load. It is not a faulty battery — it is an uncalibrated gauge reading a new cell with a different internal resistance profile. Run the full discharge-charge calibration cycle described above and confirm the phone reads 0% at automatic shutdown before the next charge.\u003c\/p\u003e\n\u003c\/div\u003e","brand":"BatteryWeb","offers":[{"title":"Warranty 1 Year","offer_id":43409499881562,"sku":"BWCS-NK5CML-1","price":21.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 2 Year","offer_id":43409499914330,"sku":"BWCS-NK5CML-2","price":24.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 3 Year","offer_id":43409499947098,"sku":"BWCS-NK5CML-3","price":26.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0674\/4775\/0746\/files\/BW-CS-NK5CML-1.webp?v=1779579815","url":"https:\/\/batteryweb.com\/products\/simvalley-xl-915-replacement-battery-37v-750mah-li-ion","provider":"BatteryWeb","version":"1.0","type":"link"}