{"product_id":"simvalley-sx-325-replacement-battery-37v-1050mah-li-ion","title":"Simvalley SX-325 Compatible Battery 3.7V 1050mAh PX-3402","description":"\u003cdiv class=\"bpw-desc\"\u003e\n  \u003ch2 class=\"bpw-desc-h2\"\u003eSimvalley SX-325 — 3.7V Li-ion Replacement Battery (PX-3402)\u003c\/h2\u003e\n\n  \u003cp class=\"bpw-desc-lead\"\u003eThis 3.7V 1050mAh lithium-ion battery is a direct replacement for the Simvalley SX-325 smartphone. It fits the OEM part numbers PX-3402, PX-3402-675, and PX-3402-912. Install it when the original cell no longer holds a charge or fails to power the handset through normal use.\u003c\/p\u003e\n\n  \u003cul class=\"bpw-desc-bullets\"\u003e\n    \u003cli\u003e\n\u003cstrong\u003eSX-325 compatibility:\u003c\/strong\u003e\n    All three OEM part variants — PX-3402, PX-3402-675, and PX-3402-912 — share the same 3.7V nominal voltage rail, connector pinout, and BMS handshake protocol. The same physical cell dimensions (58.00 × 37.05 × 5.20mm) apply across all three, so one replacement covers the full SX-325 production run.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eBench tested on actual hardware:\u003c\/strong\u003e\n    We cycled this cell through a full discharge-to-cutoff and charge-to-termination sequence on the SX-325 platform. The BMS accepted charge termination correctly, and protection circuits triggered at expected voltage thresholds with no false cutoffs.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eFuel gauge recalibration after swap:\u003c\/strong\u003e\n    On first use after installing this cell, disable fast charging if your SX-325 supports it, then run one complete discharge down to auto-shutoff followed by a full charge. This lets the fuel gauge IC map its coulomb counter against the new cell's actual discharge curve before fast-charge current is applied.\u003c\/li\u003e\n  \u003c\/ul\u003e\n\n  \u003chr class=\"bpw-desc-divider\"\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eWhy the SX-325 reports wrong battery percentage after a cell swap\u003c\/h3\u003e\n\n  \u003cp class=\"bpw-desc-p\"\u003eThe SX-325 fuel gauge IC stores a charge curve calibrated to the original cell's internal impedance profile. When a new cell goes in, that stored curve no longer matches the actual discharge behaviour of the replacement — so the OS reads a percentage based on stale data. You may see the indicator sit at 100% longer than expected, then drop sharply. One full discharge-to-shutoff followed by an uninterrupted charge to 100% forces the IC to rebuild its internal model against the new cell. After that cycle, percentage reporting stabilises.\u003c\/p\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eSudden shutdown at 20–30% on the replacement cell\u003c\/h3\u003e\n\n  \u003cp class=\"bpw-desc-p\"\u003eThis happens when the cell voltage collapses under high-current load — typically when the modem transmits or the screen brightness spikes — before the fuel gauge reads zero. The new cell's open-circuit voltage looks healthy at rest, but under draw it drops below the BMS cutoff threshold before the gauge expects it. This is a fuel gauge calibration lag, not a faulty cell. Run one full cycle without fast charging: discharge to auto-shutoff, charge uninterrupted to 4.2V termination, and the shutoffs at 20–30% should stop.\u003c\/p\u003e\n\u003c\/div\u003e","brand":"BatteryWeb","offers":[{"title":"Warranty 1 Year","offer_id":43404234850394,"sku":"BWCS-SSX325SL-1","price":23.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 2 Year","offer_id":43404234883162,"sku":"BWCS-SSX325SL-2","price":26.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 3 Year","offer_id":43404234915930,"sku":"BWCS-SSX325SL-3","price":28.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0674\/4775\/0746\/files\/BW-CS-SSX325SL-1.webp?v=1779369465","url":"https:\/\/batteryweb.com\/products\/simvalley-sx-325-replacement-battery-37v-1050mah-li-ion","provider":"BatteryWeb","version":"1.0","type":"link"}