{"product_id":"tecno-spark-2-replacement-battery-38v-3200mah-li-polymer","title":"Tecno Spark 2 Replacement Battery BL-34BT 3.8V 3200mAh","description":"\u003cdiv class=\"bpw-desc\"\u003e\n  \u003ch2 class=\"bpw-desc-h2\"\u003eTecno Spark 2 (KA7 \/ KA7O) — 3.8V Li-Polymer Replacement Battery (BL-34BT)\u003c\/h2\u003e\n\n  \u003cp class=\"bpw-desc-lead\"\u003eThis is a 3.8V, 3200mAh Li-Polymer replacement battery for the Tecno Spark 2 smartphone, covering KA7 and KA7O variants. It replaces OEM part number BL-34BT. Fit this when the original cell no longer holds a useful charge or the phone shuts down unpredictably under load.\u003c\/p\u003e\n\n  \u003cul class=\"bpw-desc-bullets\"\u003e\n    \u003cli\u003e\n\u003cstrong\u003eKA7 and KA7O compatibility:\u003c\/strong\u003e\n    Both KA7 and KA7O variants use the same BL-34BT footprint — 87.70 × 64.70 × 3.60mm — with the same connector orientation and BMS handshake. No modification needed for either board revision.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eBench tested on actual hardware:\u003c\/strong\u003e\n    We ran this cell through full charge and load cycles on a KA7 board. The BMS accepted the connection without fault flags, charge current ramped correctly, and the protection circuit tripped at expected cutoff thresholds.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eFuel gauge recalibration on first use:\u003c\/strong\u003e\n    After fitting, disable fast charging and run one complete discharge-to-charge cycle at standard current. This forces the fuel gauge IC to map its coulomb counter against the new cell's actual discharge curve before any high-current session begins on an uncalibrated reference.\u003c\/li\u003e\n  \u003c\/ul\u003e\n\n  \u003chr class=\"bpw-desc-divider\"\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eWhy the Spark 2 reports wrong battery percentage after a cell swap\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eThe Spark 2 uses a fuel gauge IC that builds its state-of-charge model from accumulated charge and discharge data on the original cell. When a new cell goes in, that learned curve no longer matches the new cell's actual voltage-to-capacity relationship. The IC keeps using its old reference, so the percentage shown on screen drifts from reality. One full discharge down to automatic cutoff, followed by a full charge at standard rate, resets the coulomb counter baseline against the new cell and brings the reported percentage back into alignment.\u003c\/p\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eSudden shutdown at 20–30% charge remaining on the replacement cell\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eThis happens when the modem, display, or a background process pulls a current spike the new cell cannot sustain at that state of charge — the cell voltage drops below the BMS cutoff threshold and the phone powers off even though the fuel gauge still shows charge remaining. It is a voltage sag event, not a capacity defect. The fuel gauge IC has not yet mapped the new cell's voltage cliff, so it does not warn before shutdown. Complete two or three full discharge-charge cycles at standard rate and the gauge IC recalibrates to the correct cutoff point, typically resolving the early shutdown.\u003c\/p\u003e\n\u003c\/div\u003e","brand":"BatteryWeb","offers":[{"title":"Warranty 1 Year","offer_id":43391898714202,"sku":"BWCS-TEK200SL-1","price":26.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 2 Year","offer_id":43391898746970,"sku":"BWCS-TEK200SL-2","price":29.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 3 Year","offer_id":43391898779738,"sku":"BWCS-TEK200SL-3","price":32.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0674\/4775\/0746\/files\/BW-CS-TEK200SL-1.webp?v=1779142626","url":"https:\/\/batteryweb.com\/products\/tecno-spark-2-replacement-battery-38v-3200mah-li-polymer","provider":"BatteryWeb","version":"1.0","type":"link"}