{"product_id":"soundmaster-tr150ws-replacement-battery-37v-750mah-li-ion","title":"Soundmaster TR150WS Replacement Battery 3.7V 750mAh","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, 750mAh Li-ion cell for the Soundmaster TR150WS. It replaces the original internal battery when capacity has dropped or the cell no longer holds a charge. Dimensions are 53.00 × 33.90 × 5.70mm — confirm against your existing cell before fitting.\u003c\/p\u003e\n\n  \u003cul class=\"bpw-desc-bullets\"\u003e\n    \u003cli\u003e\n\u003cstrong\u003eTR150WS fit:\u003c\/strong\u003e\n    The TR150WS uses a single-cell Li-ion pack at 3.7V nominal. This replacement matches that voltage rail and physical footprint, so the charge IC and BMS handshake behave as expected with the device's power management logic.\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 passes, monitoring BMS cutoff at the low-voltage threshold. The protection circuit tripped correctly at the expected floor, and charge acceptance from the device's charge IC was normal across all test passes.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eFuel gauge recalibration after swap:\u003c\/strong\u003e\n    On first use after installation, disable fast charging for one complete discharge-charge cycle. This lets the fuel gauge IC build an accurate discharge curve against the new cell before high-current charging begins on an uncalibrated state-of-charge register.\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 TR150WS after a cell swap\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eThis happens because the fuel gauge IC is still reading the discharge curve of the old, degraded cell. The new cell has a steeper voltage drop near depletion, so the reported percentage and the actual cell voltage diverge. Under load — screen, radio, or data activity — the cell voltage sags below the BMS cutoff floor before the OS has time to trigger a safe shutdown. One full discharge-to-shutdown followed by an uninterrupted charge to 100% resets the coulomb counter and resolves this.\u003c\/p\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eTR150WS not powering on after sitting in storage with a flat battery\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eIf the cell has self-discharged below roughly 2.5V, the BMS locks out to prevent charging a cell that may be compromised. The device will show no response — no boot screen, no charge indicator. Connect to a wall charger rather than a PC USB port, which may not supply enough current to trigger the trickle-charge recovery path. Leave it on charge for 15–20 minutes before attempting to power on; the BMS needs to confirm the cell accepts trickle current before it releases the main charge gate.\u003c\/p\u003e\n\u003c\/div\u003e","brand":"BatteryWeb","offers":[{"title":"Warranty 1 Year","offer_id":43409500012634,"sku":"BWCS-NK5CML-1","price":21.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 2 Year","offer_id":43409500045402,"sku":"BWCS-NK5CML-2","price":24.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 3 Year","offer_id":43409500078170,"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\/soundmaster-tr150ws-replacement-battery-37v-750mah-li-ion","provider":"BatteryWeb","version":"1.0","type":"link"}