{"product_id":"airbus-thr9-replacement-battery-37v-5700mah-li-ion","title":"Airbus THR9 Replacement Battery BLN-5i 3.7V 5700mAh","description":"\u003cdiv class=\"bpw-desc\"\u003e\n  \u003ch2 class=\"bpw-desc-h2\"\u003eAirbus THR9 Series — 3.7V Li-ion Replacement Battery (BLN-5i \/ BLN-6)\u003c\/h2\u003e\n\n  \u003cp class=\"bpw-desc-lead\"\u003eThis is a 3.7V 5700mAh Li-ion replacement battery for the Airbus THR9 series portable radio. It fits the THR9, THR9i, THR9 C-30, and THR9 Ex. The OEM part numbers are BLN-5i and BLN-6.\u003c\/p\u003e\n\n  \u003cul class=\"bpw-desc-bullets\"\u003e\n    \u003cli\u003e\n\u003cstrong\u003eTHR9 series fit — all four variants:\u003c\/strong\u003e\n    The THR9, THR9i, THR9 C-30, and THR9 Ex share the same battery bay dimensions, connector pinout, and BMS handshake protocol. One pack covers the full platform — no adapter or modification needed.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eBench tested on actual hardware:\u003c\/strong\u003e\n    We ran this pack through transmit-cycle loads on the THR9 platform. The BMS held stable under repeated PTT events and the charger dock accepted the BMS handshake without a fault LED on the first insertion.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eContact strip check on first dock insertion:\u003c\/strong\u003e\n    If the charger shows a fault LED when you first seat this battery, remove the pack, wipe the gold contact strip with a dry cloth, and reseat firmly. The THR9 dock requires a clean contact cycle before it recognises a new BMS — this clears the fault in most cases without returning the unit.\u003c\/li\u003e\n  \u003c\/ul\u003e\n\n  \u003chr class=\"bpw-desc-divider\"\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eWhy the THR9 cuts out mid-transmission on a new BLN-5i\u003c\/h3\u003e\n\n  \u003cp class=\"bpw-desc-p\"\u003eA new cell ships at storage voltage — typically 3.6V to 3.85V, not a full charge. When the THR9 keys up to transmit, current draw spikes sharply. If the cell voltage at that moment sits below the BMS transmit threshold, the BMS trips the output to protect the cell. This looks like a mid-transmission dropout but it is not a faulty pack. Charge the battery fully before first operational use and the BMS will hold through normal PTT events.\u003c\/p\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eBar indicator showing one fewer bar than expected after fitting the BLN-5i\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eThe THR9 reads battery level using voltage-threshold steps — each bar corresponds to a voltage band. A new pack at storage voltage sits in the second or third band, so the indicator shows one or two bars short of full on first power-up. This is not a capacity defect. Put the pack through a full charge cycle in the THR9 dock and let it reach 4.2V before checking the bar indicator again.\u003c\/p\u003e\n\u003c\/div\u003e","brand":"BatteryWeb","offers":[{"title":"Warranty 1 Year","offer_id":43426298495066,"sku":"BWCS-ETH920TW-1","price":45.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 2 Year","offer_id":43426298527834,"sku":"BWCS-ETH920TW-2","price":53.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 3 Year","offer_id":43426298560602,"sku":"BWCS-ETH920TW-3","price":59.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0674\/4775\/0746\/files\/BW-CS-ETH920TW-1.webp?v=1779930583","url":"https:\/\/batteryweb.com\/products\/airbus-thr9-replacement-battery-37v-5700mah-li-ion","provider":"BatteryWeb","version":"1.0","type":"link"}