{"product_id":"kpn-messenger-2-replacement-battery-37v-1000mah-li-ion","title":"HB4H1 KPN Messenger 2 Compatible Battery 3.7V 1000mAh","description":"\u003cdiv class=\"bpw-desc\"\u003e\n  \u003ch2 class=\"bpw-desc-h2\"\u003eKPN Messenger 2 — 3.7V Li-ion Replacement Battery (HB4H1)\u003c\/h2\u003e\n\n  \u003cp class=\"bpw-desc-lead\"\u003eThis is a 3.7V, 1000mAh Li-ion battery for the KPN Messenger 2 smartphone. It matches the OEM HB4H1 specification and fits the original battery slot without modification. Voltage and cell chemistry match the original exactly at 3.7V \/ 3.7Wh.\u003c\/p\u003e\n\n  \u003cul class=\"bpw-desc-bullets\"\u003e\n    \u003cli\u003e\n\u003cstrong\u003eKPN Messenger 2 compatibility:\u003c\/strong\u003e\n    The Messenger 2 uses a single-cell Li-ion pack running a 3.7V nominal rail. The HB4H1 form factor — 59.67 × 39.66 × 4.26mm — matches the chassis bay directly, and the connector pinout aligns with the phone's charge IC and fuel gauge IC wiring.\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 the bench, confirming the BMS communicates correctly with the charge IC and that cell voltage holds stable across screen-on and modem-active load states. No spurious cutoffs were recorded during testing.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eFuel gauge recalibration on first cycle:\u003c\/strong\u003e\n    After fitting a new cell, run one full discharge to 5–10% then charge uninterrupted to 100% before using fast charging. The Messenger 2's fuel gauge IC needs this cycle to map its coulomb counter against the new cell's actual discharge curve — skipping it causes inaccurate percentage readings early on.\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 KPN Messenger 2 after a cell swap\u003c\/h3\u003e\n\n  \u003cp class=\"bpw-desc-p\"\u003eThis is a voltage cliff issue, not a capacity fault. Under combined modem and display load, the cell voltage drops faster than the fuel gauge IC predicts — the phone hits the low-voltage cutoff threshold before the reported percentage reaches zero. It happens most often on a fresh cell because the fuel gauge IC is still calibrated to the old cell's discharge curve. One full discharge-charge cycle lets the coulomb counter recalibrate and the shutdowns stop. If they persist past two full cycles, check that the battery connector is fully seated — a partial contact raises internal resistance and accelerates voltage sag under load.\u003c\/p\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eKPN Messenger 2 showing erratic or jumping battery percentage after replacement\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eThe fuel gauge IC stores a learned discharge model for the old cell and does not automatically reset when a new cell is installed. Until it recalibrates, the reported percentage can jump several points up or down during normal use. This is not a faulty battery — it is the IC interpolating against a mismatched cell profile. Run the phone down to below 10% and then charge it to 100% in a single uninterrupted session. After that cycle, the percentage reading stabilises at the correct value.\u003c\/p\u003e\n\u003c\/div\u003e","brand":"BatteryWeb","offers":[{"title":"Warranty 1 Year","offer_id":43405084786778,"sku":"BWCS-HUT211SL-1","price":27.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 2 Year","offer_id":43405084819546,"sku":"BWCS-HUT211SL-2","price":31.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 3 Year","offer_id":43405084852314,"sku":"BWCS-HUT211SL-3","price":33.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0674\/4775\/0746\/files\/BW-CS-HUT211SL-1.webp?v=1779369919","url":"https:\/\/batteryweb.com\/products\/kpn-messenger-2-replacement-battery-37v-1000mah-li-ion","provider":"BatteryWeb","version":"1.0","type":"link"}