{"product_id":"jbl-free-replacement-battery-37v-1200mah-li-polymer","title":"JBL Free Replacement Battery GSP853450 3.7V 1200mAh","description":"\u003cdiv class=\"bpw-desc\"\u003e\n  \u003ch2 class=\"bpw-desc-h2\"\u003eJBL Free \/ Free X Truly Wireless — 3.7V Li-Polymer Replacement Battery (GSP853450)\u003c\/h2\u003e\n\n  \u003cp class=\"bpw-desc-lead\"\u003eThis 3.7V, 1200mAh lithium-polymer cell replaces the GSP853450 battery inside JBL Free and Free X Truly Wireless earbuds. It fits the left or right earbud housing and restores playback capacity lost to cell degradation. Dimensions are 38.00 × 36.50 × 8.00mm — measure your existing cell before ordering if you are unsure which earbud is failing.\u003c\/p\u003e\n\n  \u003cul class=\"bpw-desc-bullets\"\u003e\n    \u003cli\u003e\n\u003cstrong\u003eFree and Free X compatibility:\u003c\/strong\u003e\n    Both models share the same earbud housing geometry, 3.7V power rail, and GSP853450 footprint. The BMS logic inside each earbud accepts the replacement cell without firmware intervention.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eBench tested on actual hardware:\u003c\/strong\u003e\n    We cycled the cell through charge and discharge on a Free earbud. The onboard BMS accepted the new cell, held cutoff at 4.2V charge ceiling, and triggered low-voltage protection at 3.0V with no anomalies.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eFirst-charge protocol for JBL Free earbuds:\u003c\/strong\u003e\n    After fitting the new cell, place the earbud in the charging case and leave it for a complete charge cycle before pairing. The earbud's fuel gauge resets its capacity estimate during this first session — skipping it causes the battery indicator to misread remaining charge.\u003c\/li\u003e\n  \u003c\/ul\u003e\n\n  \u003chr class=\"bpw-desc-divider\"\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eWhy JBL Free earbuds cut out mid-audio after a battery swap\u003c\/h3\u003e\n\n  \u003cp class=\"bpw-desc-p\"\u003eThe Free earbud runs Bluetooth radio, audio decoding, and touch sensor logic from a single 3.7V cell. Under combined load, a cell sitting below 3.6V can sag just enough to trigger the BMS undervoltage cutoff — even if the case indicator shows charge remaining. This is most common when the replacement cell ships at storage voltage around 3.7–3.8V and has not yet been fully cycled. A complete charge to 4.2V before first use stabilises the voltage floor and eliminates most cutout events.\u003c\/p\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eCharging case shows full but earbud dies quickly after replacement\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eThe charging case reads the earbud's reported state-of-charge, not the raw cell voltage — so a new cell at storage voltage can report \"full\" before it has completed a real cycle. The fuel gauge inside the earbud recalibrates over the first three to five full charge-discharge cycles. Until then, actual usable capacity will read lower than the cell's rated 1200mAh. Run three full cycles — charge to 4.2V, use until the earbud auto-powers off — and the indicator will align with real cell state.\u003c\/p\u003e\n\u003c\/div\u003e","brand":"BatteryWeb","offers":[{"title":"Warranty 1 Year","offer_id":43428096999514,"sku":"BWCS-JBF100SL-1","price":33.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 2 Year","offer_id":43428097032282,"sku":"BWCS-JBF100SL-2","price":39.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 3 Year","offer_id":43428097065050,"sku":"BWCS-JBF100SL-3","price":43.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0674\/4775\/0746\/files\/BW-CS-JBF100SL-1.webp?v=1779934061","url":"https:\/\/batteryweb.com\/products\/jbl-free-replacement-battery-37v-1200mah-li-polymer","provider":"BatteryWeb","version":"1.0","type":"link"}