{"product_id":"gp-replacement-battery-36v-400mah-ni-mh","title":"GP T306 Cordless Phone Replacement Battery 3.6V 400mAh","description":"\u003cdiv class=\"bpw-desc\"\u003e\n  \u003ch2 class=\"bpw-desc-h2\"\u003eGP T306 — 3.6V Ni-MH Replacement Battery (T306)\u003c\/h2\u003e\n\n  \u003cp class=\"bpw-desc-lead\"\u003eThis is a 3.6V, 400mAh Ni-MH replacement battery for cordless phone handsets using the T306 battery format. It replaces GP part numbers T306, 4M3EMJZ, and F6M3EMX. If your handset no longer holds a charge or drops out of range faster than it used to, this is the cell that brings it back.\u003c\/p\u003e\n\n  \u003cul class=\"bpw-desc-bullets\"\u003e\n    \u003cli\u003e\n\u003cstrong\u003eT306 format handsets:\u003c\/strong\u003e\n    Cordless phones using this battery share the same 3.6V NiMH cell footprint, connector orientation, and voltage floor. The base station charger circuit expects this specific chemistry and voltage range — swapping in a lithium cell will not work and can damage the charging circuit.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eBench tested on actual hardware:\u003c\/strong\u003e\n    We ran this cell through a full charge-discharge cycle on a DECT handset base. The BMS accepted the cell without error, and charge current stepped down correctly at full capacity. Voltage held steady across multiple discharge cycles.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eFirst charge after installation:\u003c\/strong\u003e\n    After installing, seat the handset in the base for a full 16-hour slow charge before first use. NiMH cells ship in a partially discharged state. Skipping this step leaves capacity on the table — the cell won't reach rated 400mAh until it completes a proper initial conditioning cycle.\u003c\/li\u003e\n  \u003c\/ul\u003e\n\n  \u003chr class=\"bpw-desc-divider\"\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eBase station showing no charge or error light after battery swap\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eNiMH batteries lose voltage during storage. If the cell arrives below roughly 3.0V, some DECT base station charger circuits read it as a fault and refuse to begin charging. The base isn't broken — it's rejecting a cell that sits outside its acceptance window. Place the handset firmly in the base and leave it for up to 30 minutes; most chargers will attempt a trickle pre-charge to bring the voltage up before switching to full charge mode. If the error light clears within that window, the cycle has started normally.\u003c\/p\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eHandset not re-pairing with base after battery replacement\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eSome DECT phones store pairing data in volatile memory that resets when power is fully removed — which is exactly what happens during a battery swap. The handset comes back up with no active link to the base. This is not a battery fault. Re-register the handset using your phone's pairing or registration procedure, typically held button on the base for 5–10 seconds, then confirm on the handset within 60 seconds.\u003c\/p\u003e\n\u003c\/div\u003e","brand":"BatteryWeb","offers":[{"title":"Warranty 1 Year","offer_id":43340000231514,"sku":"BWCS-CPT306CL-1","price":22.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 2 Year","offer_id":43340000264282,"sku":"BWCS-CPT306CL-2","price":25.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 3 Year","offer_id":43340000297050,"sku":"BWCS-CPT306CL-3","price":28.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0674\/4775\/0746\/files\/BW-CS-CPT306CL_1.webp?v=1778367024","url":"https:\/\/batteryweb.com\/products\/gp-replacement-battery-36v-400mah-ni-mh","provider":"BatteryWeb","version":"1.0","type":"link"}