{"product_id":"soundmaster-replacement-battery-37v-1050mah-li-ion","title":"Soundmaster TR150WS Replacement Battery 3.7V 1050mAh","description":"\u003cdiv class=\"bpw-desc\"\u003e\n  \u003ch2 class=\"bpw-desc-h2\"\u003eSoundmaster TR150WS — 3.7V Li-ion Replacement Battery\u003c\/h2\u003e\n\n  \u003cp class=\"bpw-desc-lead\"\u003eThis is a 3.7V, 1050mAh Li-ion replacement cell for the Soundmaster TR150WS mobile device. It slots in when the original cell has degraded past the point of holding a usable charge. Voltage and physical dimensions — 53.00 x 33.90 x 5.60mm — match the original specification.\u003c\/p\u003e\n\n  \u003cul class=\"bpw-desc-bullets\"\u003e\n    \u003cli\u003e\n\u003cstrong\u003eTR150WS platform fit:\u003c\/strong\u003e\n    The TR150WS cell uses a fixed form factor tied to the original PCB connector layout and BMS handshake voltage thresholds. Swapping in a mismatched cell — even at the same nominal voltage — can cause the charge IC to reject the cell or report inaccurate capacity to the OS.\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 the bench, confirming the BMS accepted charge current without fault flags and that the protection circuit tripped correctly at the low-voltage cutoff threshold.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eFuel gauge recalibration after installation:\u003c\/strong\u003e\n    On first use, disable fast charging and run one full discharge-to-charge cycle from 100% to near-empty and back. This lets the fuel gauge IC map the new cell's discharge curve before the OS begins interpolating percentage from an uncalibrated coulomb 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 TR150WS reports wrong battery percentage after a cell swap\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eThe fuel gauge IC stores a learned discharge curve from the old cell. When a new cell goes in, that curve no longer matches the actual cell chemistry, so the percentage reading drifts — sometimes by 10–20%. The fix is a full calibration cycle: charge to 100%, discharge fully under normal use, then charge back to 100% without interruption. After one complete cycle the coulomb counter resets its reference points against the new cell and the percentage display stabilises.\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 fuel gauge IC is still running against the old cell's voltage curve and the device hits the hardware low-voltage cutoff before the displayed percentage reaches zero. The modem or screen draws a current spike the degraded calibration doesn't account for, and the cell voltage drops below the BMS cutoff threshold instantly. Run the calibration cycle described above — one full discharge and recharge with fast charging disabled. After that cycle, shutdowns in this percentage range should stop.\u003c\/p\u003e\n\u003c\/div\u003e","brand":"BatteryWeb","offers":[{"title":"Warranty 1 Year","offer_id":43405112180826,"sku":"BWCS-HFC250SL-1","price":21.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 2 Year","offer_id":43405112213594,"sku":"BWCS-HFC250SL-2","price":24.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 3 Year","offer_id":43405112246362,"sku":"BWCS-HFC250SL-3","price":26.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0674\/4775\/0746\/files\/BW-CS-HFC250SL-1.webp?v=1779369992","url":"https:\/\/batteryweb.com\/products\/soundmaster-replacement-battery-37v-1050mah-li-ion","provider":"BatteryWeb","version":"1.0","type":"link"}