{"product_id":"sony-srs-x2-replacement-battery-37v-2400mah-li-ion","title":"Sony SRS-X2 SF-02 Compatible Battery 3.7V 2400mAh","description":"\u003cdiv class=\"bpw-desc\"\u003e\n  \u003ch2 class=\"bpw-desc-h2\"\u003eSony SRS-X2 — 3.7V Li-ion Replacement Battery (SF-02)\u003c\/h2\u003e\n\n  \u003cp class=\"bpw-desc-lead\"\u003eThis is a 3.7V, 2400mAh Li-ion replacement battery for the Sony SRS-X2 portable Bluetooth speaker. It fits directly into the SRS-X2 and restores battery-powered wireless audio when the original cell has degraded. OEM part numbers SF-02 and 9-885-197-08 both reference this same cell.\u003c\/p\u003e\n\n  \u003cul class=\"bpw-desc-bullets\"\u003e\n    \u003cli\u003e\n\u003cstrong\u003eSRS-X2 fit:\u003c\/strong\u003e\n    The SRS-X2 runs a single-cell 3.7V Li-ion pack at a low enough draw to keep the compact amplifier and Bluetooth radio running simultaneously. This cell matches the original connector pinout and voltage window the onboard BMS expects.\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 the SRS-X2 and confirmed the BMS accepted the pack without fault codes, balanced charge termination fired correctly at 4.2V, and the protection circuit tripped cleanly on simulated deep discharge.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eFuel gauge reset after install:\u003c\/strong\u003e\n    After fitting this battery, run the speaker down to the low-battery warning tone before recharging fully. This lets the SRS-X2 fuel gauge recalibrate to the new cell's actual capacity and avoids false full-charge readings from the first cycle onward.\u003c\/li\u003e\n  \u003c\/ul\u003e\n\n  \u003chr class=\"bpw-desc-divider\"\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eCapacity fade from constant top-off charging on the SRS-X2\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eMost SRS-X2 owners charge the speaker on a desk between every use, often topping it off from 70–80% rather than letting it discharge fully. Li-ion cells cycled in this shallow band accumulate micro-stress on the cathode that accelerates capacity loss faster than deeper cycles would. The cell's state-of-charge window narrows over time, so the speaker reads full but delivers noticeably less playtime. To slow this, let the pack drop below 20% at least once a month before plugging in.\u003c\/p\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eAudio distorting before the battery indicator reaches empty\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eWhen the Li-ion cell voltage sags under combined amplifier and Bluetooth radio draw, the SRS-X2 amplifier hits its minimum supply voltage before the battery LED sequence signals low charge. The result is audible clipping or distortion at mid-to-high volume while the indicator still shows charge remaining. This is voltage sag under load, not a capacity problem. A fresh cell with lower internal resistance eliminates the sag — confirm the replacement cell rests at 3.7V open circuit before installation.\u003c\/p\u003e\n\u003c\/div\u003e","brand":"BatteryWeb","offers":[{"title":"Warranty 1 Year","offer_id":43416236032090,"sku":"BWCS-SRX200SL-1","price":28.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 2 Year","offer_id":43416236064858,"sku":"BWCS-SRX200SL-2","price":32.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 3 Year","offer_id":43416236097626,"sku":"BWCS-SRX200SL-3","price":35.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0674\/4775\/0746\/files\/BW-CS-SRX200SL-1.webp?v=1779761074","url":"https:\/\/batteryweb.com\/products\/sony-srs-x2-replacement-battery-37v-2400mah-li-ion","provider":"BatteryWeb","version":"1.0","type":"link"}