{"product_id":"sunmi-m2-replacement-battery-38v-3000mah-li-polymer","title":"Sunmi M2 Payment Terminal Compatible Battery 3.8V 3000mAh","description":"\u003cdiv class=\"bpw-desc\"\u003e\n  \u003ch2 class=\"bpw-desc-h2\"\u003eSunmi M2 \/ T7820 — 3.8V Li-Polymer Replacement Battery (JKHS)\u003c\/h2\u003e\n\n  \u003cp class=\"bpw-desc-lead\"\u003eThis is a 3.8V, 3000mAh Li-Polymer battery for the Sunmi M2 and T7820 payment terminals. It replaces OEM part number JKHS and slots directly into the battery bay on both models. Capacity is 3000mAh (11.4Wh), matching the original cell specification.\u003c\/p\u003e\n\n  \u003cul class=\"bpw-desc-bullets\"\u003e\n    \u003cli\u003e\n\u003cstrong\u003eM2 and T7820 compatibility:\u003c\/strong\u003e\n    Both terminals share the same battery bay geometry, connector pinout, and BMS handshake protocol — one cell covers both models without modification.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eBench tested on actual hardware:\u003c\/strong\u003e\n    We cycled this cell through the Sunmi boot sequence and ran multiple transaction loads including receipt printer motor draws. The BMS held voltage within spec and did not trip on printer activation.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eFirst deployment tip:\u003c\/strong\u003e\n    After fitting the battery, complete one full transaction cycle before going live. The terminal maps battery capacity during normal operation and needs at least one complete power cycle to display an accurate charge indicator.\u003c\/li\u003e\n  \u003c\/ul\u003e\n\n  \u003chr class=\"bpw-desc-divider\"\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eTerminal rebooting mid-transaction after battery swap\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eThe Sunmi M2 receipt printer draws a short, sharp current spike when it fires. On a new battery that hasn't completed its first charge-discharge cycle, the BMS may read that spike as an overcurrent event and cut output. This is a calibration issue, not a fault with the cell. Run the terminal through two or three complete transaction cycles — print included — and the BMS will normalise its overcurrent threshold. If reboots persist past the third cycle, check that the battery connector is fully seated and reading at least 3.7V at rest.\u003c\/p\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eSunmi M2 won't power on after sitting unused in storage\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eLi-Polymer cells self-discharge slowly in storage. If the terminal has sat unused for several weeks or months, the cell voltage may have dropped below the BMS recovery threshold — typically around 2.5V — and the terminal will show no response at all. Connect the charging cable and leave it for 20–30 minutes without pressing the power button. The charge IC needs time to trickle-charge the cell back above the recovery threshold before the BMS will allow a normal boot. Once the screen shows a charging indicator, allow a full charge to 4.2V before powering on.\u003c\/p\u003e\n\u003c\/div\u003e","brand":"BatteryWeb","offers":[{"title":"Warranty 1 Year","offer_id":43415922901082,"sku":"BWCS-SMP782BL-1","price":45.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 2 Year","offer_id":43415922933850,"sku":"BWCS-SMP782BL-2","price":53.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 3 Year","offer_id":43415922966618,"sku":"BWCS-SMP782BL-3","price":59.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0674\/4775\/0746\/files\/BW-CS-SMP782BL-1.webp?v=1779757974","url":"https:\/\/batteryweb.com\/products\/sunmi-m2-replacement-battery-38v-3000mah-li-polymer","provider":"BatteryWeb","version":"1.0","type":"link"}