{"product_id":"vertex-standard-vx-820-replacement-battery-74v-2200mah-li-ion","title":"Vertex Standard VX-820 FNB-V86LI Replacement Battery 7.4V 2200mAh","description":"\u003cdiv class=\"bpw-desc\"\u003e\n  \u003ch2 class=\"bpw-desc-h2\"\u003eVertex Standard VX-820 Series — 7.4V Li-ion Replacement Battery (FNB-V86LI)\u003c\/h2\u003e\n\n  \u003cp class=\"bpw-desc-lead\"\u003eThis 7.4V, 2200mAh Li-ion pack replaces the FNB-V86LI, FNB-V87LI, and FNB-V86 batteries in Vertex Standard portable radios. It fits the VX-820, VX-821, VX-824, and VX-829, along with six additional models in that lineup. The connector, contact strip, and BMS handshake protocol match the original factory specification.\u003c\/p\u003e\n\n  \u003cul class=\"bpw-desc-bullets\"\u003e\n    \u003cli\u003e\n\u003cstrong\u003eVX-820 series platform fit:\u003c\/strong\u003e\n    These models share the same battery bay dimensions, gold contact layout, and BMS communication protocol. One pack covers the full range because Vertex Standard kept the battery interface consistent across the VX-820 family.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eBench tested on actual hardware:\u003c\/strong\u003e\n    We ran this pack through a full charge cycle on a VX-820 dock and monitored the BMS handshake. The protection circuit responded correctly to transmit-current spikes and returned to normal charging state without fault flags.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eFirst insertion on the dock:\u003c\/strong\u003e\n    If the charger shows a fault LED on the first insertion, remove the pack and wipe the gold contact strip with a dry cloth before reseating. The VX-820 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 VX-820 cuts out mid-transmission on a new battery\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eA new Li-ion cell ships at storage voltage — typically around 3.7V per cell, not the 4.2V full-charge peak. Under transmit load, that lower starting voltage drops further, and the BMS can trip its undervoltage cutoff before the radio completes the transmission. This is not a defective pack. A full charge cycle before first use brings both cells to 4.2V and gives the BMS its full working headroom during PTT events.\u003c\/p\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eBar indicator showing one fewer bar than expected after full charge\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eThe VX-820 uses a fixed voltage-threshold display — each bar maps to a voltage band, not a capacity percentage. A new pack fresh off its first charge cycle may read one bar short because the cells haven't completed their initial conditioning. Run two full discharge-and-charge cycles and the resting voltage will stabilise at the correct threshold. After conditioning, the indicator should hold at full bars until the pack voltage drops below approximately 7.0V under load.\u003c\/p\u003e\n\u003c\/div\u003e","brand":"BatteryWeb","offers":[{"title":"Warranty 1 Year","offer_id":43426351251546,"sku":"BWCS-FNB86TW-1","price":40.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 2 Year","offer_id":43426351284314,"sku":"BWCS-FNB86TW-2","price":47.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 3 Year","offer_id":43426351317082,"sku":"BWCS-FNB86TW-3","price":52.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0674\/4775\/0746\/files\/BW-CS-FNB86TW-1.webp?v=1779930807","url":"https:\/\/batteryweb.com\/products\/vertex-standard-vx-820-replacement-battery-74v-2200mah-li-ion","provider":"BatteryWeb","version":"1.0","type":"link"}