{"product_id":"sena-gt-air-ii-replacement-battery-37v-800mah-li-polymer","title":"Sena GT-Air II Replacement Battery PTC802050 3.7V 800mAh","description":"\u003cdiv class=\"bpw-desc\"\u003e\n  \u003ch2 class=\"bpw-desc-h2\"\u003eSena GT-Air II \/ J-Cruise II \/ SHOEI Neotec II — 3.7V Li-Polymer Replacement Battery (PTC802050)\u003c\/h2\u003e\n\n  \u003cp class=\"bpw-desc-lead\"\u003eThis is a 3.7V 800mAh Li-Polymer cell that replaces part number PTC802050 in Sena's motorcycle helmet communication systems. It fits the GT-Air II, J-Cruise II, SHOEI Neotec II, and SRL-01 (SP51) headset units. Voltage and capacity match the original spec exactly.\u003c\/p\u003e\n\n  \u003cul class=\"bpw-desc-bullets\"\u003e\n    \u003cli\u003e\n\u003cstrong\u003eGT-Air II, J-Cruise II, SHOEI Neotec II, SRL-01 (SP51) compatibility:\u003c\/strong\u003e\n    These units share the same 3.7V power rail, physical cell dimensions (52 × 20 × 8mm), and BMS handshake protocol — which is why a single cell covers all four platforms without modification.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eBench tested on actual hardware:\u003c\/strong\u003e\n    We ran this cell through charge and discharge cycles on a GT-Air II unit. The BMS accepted the pack without a fault flag, and the Bluetooth and intercom radio drew current cleanly across the full discharge curve.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eFirst-cycle protocol for helmet headsets:\u003c\/strong\u003e\n    Seat the headset in its charging cradle and run a complete charge cycle before the first ride. The GT-Air II's firmware logs the new cell during that first full cycle — skipping it causes the battery indicator to misread state-of-charge for weeks.\u003c\/li\u003e\n  \u003c\/ul\u003e\n\n  \u003chr class=\"bpw-desc-divider\"\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eWhy the GT-Air II cuts out mid-transmission on a new battery\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eThe GT-Air II runs Bluetooth audio and the intercom radio simultaneously during group rides. That combined draw creates brief current spikes that can trip the BMS on a cell that hasn't completed its first conditioning cycle. The BMS interprets the spike as an over-current event and cuts the output rail to protect the cell. After two or three full charge-discharge cycles, the BMS recalibrates its cutoff threshold to the actual cell characteristics and the drop-outs stop.\u003c\/p\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eHelmet shows full charge on the cradle but headset dies early in a ride\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eA new Li-Polymer cell ships at storage voltage — roughly 3.6–3.7V — not at full charge. If the cradle sees that voltage and reports the battery as charged, the headset enters the ride with less capacity than expected. Seat the unit in the cradle and confirm the charging LED cycles through its full sequence before removing it. The cell needs to reach 4.2V to be genuinely full.\u003c\/p\u003e\n\u003c\/div\u003e","brand":"BatteryWeb","offers":[{"title":"Warranty 1 Year","offer_id":43428107157594,"sku":"BWCS-SSP510SL-1","price":23.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 2 Year","offer_id":43428107190362,"sku":"BWCS-SSP510SL-2","price":26.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 3 Year","offer_id":43428107223130,"sku":"BWCS-SSP510SL-3","price":28.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0674\/4775\/0746\/files\/BW-CS-SSP510SL_1.webp?v=1779934133","url":"https:\/\/batteryweb.com\/products\/sena-gt-air-ii-replacement-battery-37v-800mah-li-polymer","provider":"BatteryWeb","version":"1.0","type":"link"}