{"product_id":"wm-systems-wmp-300-replacement-battery-37v-850mah-li-polymer","title":"WM Systems WMP 300 GPS Navigator Replacement Battery 3.7V 850mAh","description":"\u003cdiv class=\"bpw-desc\"\u003e\n  \u003ch2 class=\"bpw-desc-h2\"\u003eWM Systems WMP 300 — 3.7V Li-Polymer Replacement Battery (BP85A)\u003c\/h2\u003e\n\n  \u003cp class=\"bpw-desc-lead\"\u003eThis 3.7V 850mAh Li-Polymer cell replaces the original battery in the WM Systems WMP 300 and WMP-300 GPS navigator. It matches the OEM part number BP85A (1ICP7\/31\/52) and fits the same footprint at 51.80 × 30.22 × 5.70mm. Swap it in when the original cell no longer holds a charge or powers the unit through a full navigation session.\u003c\/p\u003e\n\n  \u003cul class=\"bpw-desc-bullets\"\u003e\n    \u003cli\u003e\n\u003cstrong\u003eWMP 300 \/ WMP-300 fit:\u003c\/strong\u003e\n    Both model variants use the same board layout, connector, and 3.7V voltage rail. The BP85A cell works across both without modification — the BMS reads the same charge profile on either unit.\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 a GPS navigator platform. The BMS accepted full charge without fault flags, and the protection circuit tripped correctly at the low-voltage cutoff threshold — no false shutoffs during normal draw.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eFirst-fix cold start after battery swap:\u003c\/strong\u003e\n    After fitting this cell, power the WMP 300 fully on outdoors and let it acquire a satellite fix before relying on it. GPS units perform a cold start after any full power interruption — first fix can take 5–10 minutes while the receiver rebuilds its almanac. Subsequent warm starts run under a minute.\u003c\/li\u003e\n  \u003c\/ul\u003e\n\n  \u003chr class=\"bpw-desc-divider\"\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eWMP 300 shutting off without warning at low battery\u003c\/h3\u003e\n\n  \u003cp class=\"bpw-desc-p\"\u003eThe WMP 300 battery indicator is calibrated against the original cell's discharge curve. A replacement cell with a slightly different curve can cause the unit to hit the hardware low-voltage cutoff before the on-screen warning triggers. The BMS cuts power at roughly 3.0V to protect the cell — the display may still show one bar at that point. Run two or three full charge-discharge cycles after fitting the new cell to let the device recalibrate its fuel gauge against the actual discharge curve.\u003c\/p\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eGPS accuracy dropping during active navigation on this battery\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eSome GPS navigators reduce receiver sensitivity as battery voltage sags toward the low end of the discharge curve — this is a firmware power-saving measure, not a fault with the cell. If position accuracy drops noticeably mid-route, check the battery indicator. Above 3.5V the receiver runs at full sensitivity. Keeping screen brightness at mid-level during active navigation reduces total draw and keeps voltage higher for longer across the session.\u003c\/p\u003e\n\u003c\/div\u003e","brand":"BatteryWeb","offers":[{"title":"Warranty 1 Year","offer_id":43377585750106,"sku":"BWCS-WMP300SL-1","price":23.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 2 Year","offer_id":43377585782874,"sku":"BWCS-WMP300SL-2","price":26.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 3 Year","offer_id":43377585815642,"sku":"BWCS-WMP300SL-3","price":28.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0674\/4775\/0746\/files\/BW-CS-WMP300SL-1.webp?v=1778771747","url":"https:\/\/batteryweb.com\/products\/wm-systems-wmp-300-replacement-battery-37v-850mah-li-polymer","provider":"BatteryWeb","version":"1.0","type":"link"}