{"product_id":"doro-1350-replacement-battery-37v-900mah-li-ion","title":"Doro DBP-800B Replacement Battery 3.7V 900mAh","description":"\u003cdiv class=\"bpw-desc\"\u003e\n  \u003ch2 class=\"bpw-desc-h2\"\u003eDoro 1350 \/ 6520 Series — 3.7V Li-ion Replacement Battery (DBP-800B)\u003c\/h2\u003e\n\n  \u003cp class=\"bpw-desc-lead\"\u003eThis is a 3.7V, 900mAh Li-ion cell replacing the original DBP-800B in Doro 1350, 1361, 6520, and 6530 handsets. These phones are basic calling and texting devices aimed at users who need straightforward operation. The cell measures 53.00 × 34.00 × 4.80mm and slots in using the original back cover and contacts.\u003c\/p\u003e\n\n  \u003cul class=\"bpw-desc-bullets\"\u003e\n    \u003cli\u003e\n\u003cstrong\u003e1350 \/ 1361 \/ 6520 \/ 6530 shared battery rail:\u003c\/strong\u003e\n    These four models share the same cell footprint, contact layout, and BMS voltage thresholds. The DBP-800B and its alternate part number DBR-800B are interchangeable across all of them — no connector modification needed.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eBench tested on actual hardware:\u003c\/strong\u003e\n    We cycled this cell on a Doro 6520 and monitored BMS cutoff behaviour at both ends. The protection circuit tripped at 4.20V on charge and held cutoff at 2.75V on discharge — both within spec for the original cell.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eFuel gauge reset after installation:\u003c\/strong\u003e\n    After fitting this cell, run one complete discharge to automatic power-off, then charge uninterrupted to 100% before normal use. This lets the fuel gauge IC map the new cell's discharge curve before it starts reporting percentages.\u003c\/li\u003e\n  \u003c\/ul\u003e\n\n  \u003chr class=\"bpw-desc-divider\"\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eWhy the Doro 1350 reports wrong battery percentage after a cell swap\u003c\/h3\u003e\n\n  \u003cp class=\"bpw-desc-p\"\u003eThe fuel gauge IC on these Doro handsets stores a learned discharge curve from the original cell. When a new cell goes in, the IC still references that old curve. The reported percentage drifts — the phone may show 40% and shut down, or sit at 100% longer than expected. One full discharge-charge cycle overwrites the stored curve with data from the new cell. After that cycle, percentage readings stabilise.\u003c\/p\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eSudden shutdown at 20–30% on the Doro 6520 after battery replacement\u003c\/h3\u003e\n\n  \u003cp class=\"bpw-desc-p\"\u003eThis happens when the fuel gauge IC hasn't yet calibrated to the new cell's voltage-versus-capacity curve. Under load — particularly during a call, when the modem draws a sharp current spike — the cell voltage drops faster than the IC expects, and the BMS cuts output to protect the cell. The phone reads 25% but the cell is already near its lower threshold. Running that first full discharge cycle recalibrates the coulomb counter and eliminates the premature cutoff. If shutdowns persist after two full cycles, check that the battery contacts are clean and making firm contact — a high-resistance connection causes the same voltage sag under modem load.\u003c\/p\u003e\n\u003c\/div\u003e","brand":"BatteryWeb","offers":[{"title":"Warranty 1 Year","offer_id":43391923945562,"sku":"BWCS-DEP401SL-1","price":23.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 2 Year","offer_id":43391923978330,"sku":"BWCS-DEP401SL-2","price":27.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 3 Year","offer_id":43391924011098,"sku":"BWCS-DEP401SL-3","price":29.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0674\/4775\/0746\/files\/BW-CS-DEP401SL-1.webp?v=1779142677","url":"https:\/\/batteryweb.com\/products\/doro-1350-replacement-battery-37v-900mah-li-ion","provider":"BatteryWeb","version":"1.0","type":"link"}