{"product_id":"stereoman-isi-v2-replacement-battery-37v-350mah-li-polymer","title":"STEREOMAN ISI V2 Replacement Battery 3.7V 350mAh Li-Polymer","description":"\u003cdiv class=\"bpw-desc\"\u003e\n  \u003ch2 class=\"bpw-desc-h2\"\u003eSTEREOMAN ISI V2 — 3.7V Li-Polymer Replacement Battery (MLP503131P)\u003c\/h2\u003e\n\n  \u003cp class=\"bpw-desc-lead\"\u003eThis 3.7V, 350mAh lithium-polymer cell replaces the original battery in the STEREOMAN ISI V2 true wireless earbud. It fits the ISI V2 across model variants 0000\/9128 and 0001\/9128. Capacity matches the factory specification — 1.3Wh total energy.\u003c\/p\u003e\n\n  \u003cul class=\"bpw-desc-bullets\"\u003e\n    \u003cli\u003e\n\u003cstrong\u003eISI V2 variant fit (0000\/9128 and 0001\/9128):\u003c\/strong\u003e\n    Both variants share the same battery bay geometry, connector pinout, and BMS handshake protocol. One cell covers the full production run of this model.\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 draw on the ISI V2 platform. The BMS accepted the new pack without error flags, and charge termination cut in cleanly at full voltage.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eFirst charge after fitting:\u003c\/strong\u003e\n    Seat the earbud in the charging case and run a full charge cycle before use. The ISI V2 case needs to complete one full handshake cycle with a new cell before the charge indicator reads accurately.\u003c\/li\u003e\n  \u003c\/ul\u003e\n\n  \u003chr class=\"bpw-desc-divider\"\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eWhy the ISI V2 cuts out mid-call on a new battery\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eThe ISI V2 draws current from two loads simultaneously — the audio codec and the Bluetooth radio. Under combined load, a new cell sitting at storage voltage (typically 3.6–3.7V) can sag briefly below the BMS cutoff threshold. The protection circuit reads this as undervoltage and disconnects. Running two full charge-discharge cycles brings the cell up to working voltage and tightens the BMS window, eliminating the false trips.\u003c\/p\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eCharging case shows full but earbud dies after a few minutes of use\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eThis happens when the replacement cell arrives at storage voltage and the case terminates the charge early — it sees the cell voltage rise quickly and stops before the cell is truly full. The earbud then runs off a shallow charge, not a full one. Fix this by placing the earbud in the case with the lid closed for a full uninterrupted charge cycle — at least 90 minutes from a known-flat state. After that first complete cycle, the case charge indicator will track accurately against the actual cell state.\u003c\/p\u003e\n\u003c\/div\u003e","brand":"BatteryWeb","offers":[{"title":"Warranty 1 Year","offer_id":43428125704282,"sku":"BWCS-SMX240SL-1","price":30.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 2 Year","offer_id":43428125737050,"sku":"BWCS-SMX240SL-2","price":34.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 3 Year","offer_id":43428125769818,"sku":"BWCS-SMX240SL-3","price":37.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0674\/4775\/0746\/files\/BW-CS-SMX240SL-1.webp?v=1779934245","url":"https:\/\/batteryweb.com\/products\/stereoman-isi-v2-replacement-battery-37v-350mah-li-polymer","provider":"BatteryWeb","version":"1.0","type":"link"}