{"product_id":"t-mobile-mytouch-replacement-battery-37v-1500mah-li-ion","title":"HB5N1 T-Mobile myTouch Replacement Battery 3.7V 1500mAh","description":"\u003cdiv class=\"bpw-desc\"\u003e\n  \u003ch2 class=\"bpw-desc-h2\"\u003eT-Mobile myTouch Series — 3.7V Li-ion Replacement Battery (HB5N1)\u003c\/h2\u003e\n\n  \u003cp class=\"bpw-desc-lead\"\u003eThis is a 3.7V, 1500mAh Li-ion battery for the T-Mobile myTouch and myTouch Q lineup, including the myTouch Q U8730 and myTouch U8680. It replaces the OEM HB5N1 and HB5N1H cells. Fit the physical footprint at 51.30 × 50.80 × 5.60mm — confirm before ordering if your variant isn't listed.\u003c\/p\u003e\n\n  \u003cul class=\"bpw-desc-bullets\"\u003e\n    \u003cli\u003e\n\u003cstrong\u003emyTouch and myTouch Q compatibility:\u003c\/strong\u003e\n    The U8680 and U8730 share the same battery bay dimensions, connector pinout, and BMS handshake protocol. Both accept the HB5N1 cell without modification to the contact plate or housing.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eBench tested on actual hardware:\u003c\/strong\u003e\n    We cycled this cell through full charge and discharge on the myTouch platform. The BMS engaged charge termination correctly at 4.2V and held low-voltage cutoff at the expected floor — no erratic shutdowns observed during the test sequence.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eFirst-cycle fuel gauge reset:\u003c\/strong\u003e\n    After installing this battery, run one complete discharge to automatic shutdown, then charge uninterrupted to 100% before normal use. This lets the phone's fuel gauge IC map the new cell's discharge curve before it starts reporting state-of-charge to the OS.\u003c\/li\u003e\n  \u003c\/ul\u003e\n\n  \u003chr class=\"bpw-desc-divider\"\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eWhy the myTouch reports wrong battery percentage after a cell swap\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eThe fuel gauge IC in the myTouch stores a learned discharge curve from the original cell. When a new cell goes in, that stored curve no longer matches actual cell chemistry and impedance. The OS reads the IC's estimate, not the cell voltage directly, so percentages drift — sometimes reading 40% when the phone is near cutoff. One full discharge-charge cycle forces the IC to recalibrate its coulomb counter against the new cell and corrects the reporting.\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 cell voltage drops sharply under modem or screen load — a voltage cliff the fuel gauge IC didn't predict because it's still calibrated to the old cell. The phone's protection circuit cuts power before the OS can log a low-battery event, so the shutdown appears instant. It's most common in the first few cycles on a replacement cell. Run two full discharge-to-shutdown cycles and the IC's learned curve will shift to match the new cell's voltage profile, pushing the cutoff point lower.\u003c\/p\u003e\n\u003c\/div\u003e","brand":"BatteryWeb","offers":[{"title":"Warranty 1 Year","offer_id":43405039861850,"sku":"BWCS-HUM660SL-1","price":22.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 2 Year","offer_id":43405039894618,"sku":"BWCS-HUM660SL-2","price":25.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 3 Year","offer_id":43405039927386,"sku":"BWCS-HUM660SL-3","price":27.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0674\/4775\/0746\/files\/BW-CS-HUM660SL-1.webp?v=1779369842","url":"https:\/\/batteryweb.com\/products\/t-mobile-mytouch-replacement-battery-37v-1500mah-li-ion","provider":"BatteryWeb","version":"1.0","type":"link"}