{"product_id":"rexton-sgi-wl200ap-replacement-battery-37v-850mah-li-ion","title":"Rexton SGI-WL200AP Remote Control Replacement Battery 3.7V 850mAh","description":"\u003cdiv class=\"bpw-desc\"\u003e\n  \u003ch2 class=\"bpw-desc-h2\"\u003eREXTON SGI-WL200AP \/ WL200AP — 3.7V Li-ion Replacement Battery (21221-10296051)\u003c\/h2\u003e\n\n  \u003cp class=\"bpw-desc-lead\"\u003eThis is a 3.7V 850mAh Li-ion replacement battery for the REXTON SGI-WL200AP and WL200AP wireless remote controls. These remotes pair with REXTON hearing aid systems and let users adjust volume and program settings without touching the hearing aids directly. Voltage and capacity match the original cell exactly.\u003c\/p\u003e\n\n  \u003cul class=\"bpw-desc-bullets\"\u003e\n    \u003cli\u003e\n\u003cstrong\u003eSGI-WL200AP and WL200AP compatibility:\u003c\/strong\u003e\n    Both model variants use the same flat-cell form factor, 3.7V nominal rail, and OEM part number 21221-10296051. The BMS handshake and connector pinout are identical across both, so one replacement covers either device.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eBench tested on actual hardware:\u003c\/strong\u003e\n    We cycled this cell through charge and discharge on the WL200AP platform. The protection circuit tripped correctly at low-voltage cutoff and the remote resumed normal IR transmission after a full recharge — no reset procedure needed.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eSingle-cell remote tip:\u003c\/strong\u003e\n    This remote runs on one cell. If the IR signal becomes weak or intermittent before the battery reads as fully depleted, the cell may be holding surface charge without usable capacity. Replace it at that point rather than waiting for a complete shutdown.\u003c\/li\u003e\n  \u003c\/ul\u003e\n\n  \u003chr class=\"bpw-desc-divider\"\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eWhy the WL200AP stops transmitting before the battery looks dead\u003c\/h3\u003e\n\n  \u003cp class=\"bpw-desc-p\"\u003eLi-ion cells in small remotes can hold enough voltage to register as \"charged\" on the device indicator while no longer delivering the current the IR LED needs for a clean transmission. The WL200AP's IR LED draws a short burst of current each time a button is pressed — a cell with degraded internal resistance can't sustain that burst. The remote appears fine at rest but fails mid-command. Replacing the cell resolves this immediately; no re-pairing with the hearing aids is required.\u003c\/p\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eRemote not responding at all after fitting the new battery\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eThe most common cause is reversed polarity. The flat Li-ion cell in the WL200AP has a positive and negative terminal orientation that is easy to flip during install. Check that the positive terminal on the cell aligns with the positive contact marked inside the battery compartment. A reversed cell delivers zero voltage to the circuit — the remote will show no response at all. Correct the orientation and the remote will power on without any reset step.\u003c\/p\u003e\n\u003c\/div\u003e","brand":"BatteryWeb","offers":[{"title":"Warranty 1 Year","offer_id":43416099913818,"sku":"BWCS-SWL200SL-1","price":24.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 2 Year","offer_id":43416099946586,"sku":"BWCS-SWL200SL-2","price":27.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 3 Year","offer_id":43416099979354,"sku":"BWCS-SWL200SL-3","price":30.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0674\/4775\/0746\/files\/BW-CS-SWL200SL-1.webp?v=1779760285","url":"https:\/\/batteryweb.com\/products\/rexton-sgi-wl200ap-replacement-battery-37v-850mah-li-ion","provider":"BatteryWeb","version":"1.0","type":"link"}