{"product_id":"unidata-wpu-7700-replacement-battery-37v-1100mah-li-ion","title":"UniData WPU-7700 Cordless Phone Compatible Battery ICW-1000B 3.7V","description":"\u003cdiv class=\"bpw-desc\"\u003e\n  \u003ch2 class=\"bpw-desc-h2\"\u003eUniData WPU-7700 Series — 3.7V Li-ion Replacement Battery (ICW-1000B)\u003c\/h2\u003e\n\n  \u003cp class=\"bpw-desc-lead\"\u003eThis is a 3.7V, 1100mAh Li-ion replacement battery for UniData cordless DECT phones. It fits the WPU-7700, WPU-7800, WPU-7800B, and WPU-7800B-US handsets. Swap it when your original no longer holds enough charge to get through a normal day of calls.\u003c\/p\u003e\n\n  \u003cul class=\"bpw-desc-bullets\"\u003e\n    \u003cli\u003e\n\u003cstrong\u003eWPU-7700 and WPU-7800 series fit:\u003c\/strong\u003e\n    These handsets share the same battery bay geometry, 3.7V rail, and ICW-1000B connector pinout. The BMS handshake is identical across the WPU-7800B and WPU-7800B-US variants, so one part number covers the full range.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eBench tested on actual hardware:\u003c\/strong\u003e\n    We cycled this battery through charge and discharge on a WPU-7800 handset. The BMS accepted charge from the base station cradle without fault, voltage held steady across the RF transmit cycles, and the handset reported full charge correctly.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eFirst charge after installation:\u003c\/strong\u003e\n    Place the handset in the base cradle immediately after fitting this battery and leave it there for a full uninterrupted charge before making any calls. Li-ion cells shipped in a partial state need that first full charge to calibrate the handset's battery indicator accurately.\u003c\/li\u003e\n  \u003c\/ul\u003e\n\n  \u003chr class=\"bpw-desc-divider\"\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eWhy the WPU-7700 handset loses range when the battery is low\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eDECT transmitters in the WPU-7700 series draw a sharp current spike every time the handset pings the base. When the battery voltage sags — typically below 3.4V on a degraded cell — the transmit power drops and range shrinks noticeably. A new cell holds voltage flat under that RF load. If range improved immediately after fitting this battery, the old cell was collapsing under transmit draw, not a base station issue.\u003c\/p\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eHandset not pairing with the base after battery replacement\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eRemoving the old battery cuts all power to the handset. Some DECT phones in the WPU series lose their base station pairing record when power is fully interrupted. If the handset shows \"searching\" or \"no base\" after the swap, the fix is a manual re-registration — not a faulty battery. Hold the handset's registration button and trigger the base station pairing mode at the same time. The handset will re-register and resume normal operation at 1880–1900MHz DECT frequency.\u003c\/p\u003e\n\u003c\/div\u003e","brand":"BatteryWeb","offers":[{"title":"Warranty 1 Year","offer_id":43339887116378,"sku":"BWCS-UDT100SL-1","price":23.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 2 Year","offer_id":43339887149146,"sku":"BWCS-UDT100SL-2","price":26.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 3 Year","offer_id":43339887181914,"sku":"BWCS-UDT100SL-3","price":28.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0674\/4775\/0746\/files\/BW-CS-UDT100SL-1.webp?v=1778366945","url":"https:\/\/batteryweb.com\/products\/unidata-wpu-7700-replacement-battery-37v-1100mah-li-ion","provider":"BatteryWeb","version":"1.0","type":"link"}