{"product_id":"maxcom-mm135-replacement-battery-37v-900mah-li-ion","title":"MaxCom MM135 Replacement Battery 3.7V 900mAh Li-ion","description":"\u003cdiv class=\"bpw-desc\"\u003e\n  \u003ch2 class=\"bpw-desc-h2\"\u003eMaxCom MM135 \/ MM134 — 3.7V Li-ion Replacement Battery\u003c\/h2\u003e\n\n  \u003cp class=\"bpw-desc-lead\"\u003eThis is a 3.7V, 900mAh Li-ion cell for the MaxCom MM135 and MM134 mobile phones. It replaces the original battery when capacity fade makes the phone unreliable through a normal day. Dimensions are 53.00 × 34.00 × 4.30mm — confirm these against your existing cell before ordering.\u003c\/p\u003e\n\n  \u003cul class=\"bpw-desc-bullets\"\u003e\n    \u003cli\u003e\n\u003cstrong\u003eMM135 and MM134 compatibility:\u003c\/strong\u003e\n    Both models share the same battery bay dimensions, voltage rail, and connector pinout, so one cell covers both. Swapping between them requires no modification.\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 on the MM135 platform. The BMS accepted charge current normally, and the protection circuit tripped correctly at the low-voltage cutoff threshold with no anomalies.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eFuel gauge recalibration after swap:\u003c\/strong\u003e\n    After fitting this cell, run one complete discharge down to auto-shutdown, then charge to 100% uninterrupted. This lets the phone's fuel gauge IC map its readings to the new cell's discharge curve before normal use begins.\u003c\/li\u003e\n  \u003c\/ul\u003e\n\n  \u003chr class=\"bpw-desc-divider\"\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eWhy the MM135 shuts down suddenly at 20–30% after a cell swap\u003c\/h3\u003e\n\n  \u003cp class=\"bpw-desc-p\"\u003eThe MM135 fuel gauge IC stores a discharge model calibrated to the old cell's internal resistance profile. A new cell has a different voltage-versus-capacity curve, so the gauge reads 25% when the actual cell voltage is already close to the BMS cutoff threshold. Under the load of an active call or screen-on use, voltage dips briefly below the cutoff and the phone shuts off. One full discharge-to-shutdown cycle followed by an uninterrupted charge to 100% forces the coulomb counter to resync against the new cell, resolving the early shutdown behaviour.\u003c\/p\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003ePhone shows incorrect battery percentage after replacement\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eThe fuel gauge IC on the MM135 uses a stored charge curve from the previous cell — when the cell is swapped, that curve no longer matches reality and percentage readings become unreliable. You may see the indicator jump from 60% to 20% without significant use, or the phone refuse to turn on despite the gauge showing charge remaining. Drain the phone fully until it powers off on its own, then charge in a single session to 100% without interruption. After that first complete cycle, gauge accuracy returns to normal.\u003c\/p\u003e\n\u003c\/div\u003e","brand":"BatteryWeb","offers":[{"title":"Warranty 1 Year","offer_id":43405014794330,"sku":"BWCS-DEP510SL-1","price":23.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 2 Year","offer_id":43405014827098,"sku":"BWCS-DEP510SL-2","price":27.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 3 Year","offer_id":43405014859866,"sku":"BWCS-DEP510SL-3","price":29.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0674\/4775\/0746\/files\/BW-CS-DEP510SL_1.webp?v=1779369805","url":"https:\/\/batteryweb.com\/products\/maxcom-mm135-replacement-battery-37v-900mah-li-ion","provider":"BatteryWeb","version":"1.0","type":"link"}