{"product_id":"horizon-hx870-replacement-battery-74v-1100mah-li-ion","title":"Horizon HX870 Replacement Battery 7.4V 1100mAh SBR-13LI","description":"\u003cdiv class=\"bpw-desc\"\u003e\n  \u003ch2 class=\"bpw-desc-h2\"\u003eHorizon HX870 \/ HX870E — 7.4V Li-ion Replacement Battery (SBR-13LI)\u003c\/h2\u003e\n\n  \u003cp class=\"bpw-desc-lead\"\u003eThis is a 7.4V, 1100mAh Li-ion replacement battery for the Horizon HX870 and HX870E handheld marine VHF radios. It replaces OEM part SBR-13LI directly. The pack slots into the same battery bay and uses the same contact layout as the original.\u003c\/p\u003e\n\n  \u003cul class=\"bpw-desc-bullets\"\u003e\n    \u003cli\u003e\n\u003cstrong\u003eHX870 and HX870E compatibility:\u003c\/strong\u003e\n    Both models share the same battery bay geometry, contact pin spacing, and 7.4V nominal rail. The BMS handshake protocol is identical across both variants, so one pack covers either unit without modification.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eBench tested on actual hardware:\u003c\/strong\u003e\n    We ran this pack through charge and discharge cycles on the HX870 platform. The BMS handled transmit-load current spikes cleanly and did not trigger overcurrent cutoff during sustained PTT presses.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eFirst-insertion contact check:\u003c\/strong\u003e\n    If the dock LED flashes a fault code on first insertion, remove the pack, wipe the gold contact strip with a dry cloth, and reseat firmly. The HX870 charging dock requires a clean contact cycle to complete the BMS handshake before it will begin charging.\u003c\/li\u003e\n  \u003c\/ul\u003e\n\n  \u003chr class=\"bpw-desc-divider\"\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eWhy the HX870 cuts out mid-transmission on a freshly inserted battery\u003c\/h3\u003e\n\n  \u003cp class=\"bpw-desc-p\"\u003eA new Li-ion cell ships at storage voltage — typically 3.6–3.7V per cell, putting the pack around 7.2V. Under the transmit current spike when PTT is pressed, that starting voltage can sag enough to trip the radio's low-voltage cutoff before the pack has gone through its first full charge. The fix is straightforward: charge the pack fully before the first transmit session. After a complete charge cycle the resting voltage sits above 8.0V and the sag margin is restored.\u003c\/p\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eBar indicator showing one fewer bar than expected after swap\u003c\/h3\u003e\n\n  \u003cp class=\"bpw-desc-p\"\u003eThe HX870 reads battery level through simple voltage thresholds, not a fuel gauge chip. A new pack at storage voltage reads lower on those thresholds than a fully charged cell, so the radio displays one or two bars even though the pack is not depleted. This is not a cell fault or a capacity issue. Charge the pack to completion — the indicator should step up to full bars once resting voltage clears the top threshold, typically above 8.2V.\u003c\/p\u003e\n\u003c\/div\u003e","brand":"BatteryWeb","offers":[{"title":"Warranty 1 Year","offer_id":43426318450778,"sku":"BWCS-SHX870TW-1","price":36.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 2 Year","offer_id":43426318483546,"sku":"BWCS-SHX870TW-2","price":42.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 3 Year","offer_id":43426318516314,"sku":"BWCS-SHX870TW-3","price":46.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0674\/4775\/0746\/files\/BW-CS-SHX870TW-1.webp?v=1779930681","url":"https:\/\/batteryweb.com\/products\/horizon-hx870-replacement-battery-74v-1100mah-li-ion","provider":"BatteryWeb","version":"1.0","type":"link"}