{"product_id":"nintendo-dsi-replacement-battery-37v-550mah-li-polymer","title":"Nintendo DSi Replacement Battery TWL-003 3.7V 550mAh","description":"\u003cdiv class=\"bpw-desc\"\u003e\n  \u003ch2 class=\"bpw-desc-h2\"\u003eNintendo DSi \/ NDSiL — 3.7V Li-Polymer Replacement Battery (TWL-003)\u003c\/h2\u003e\n\n  \u003cp class=\"bpw-desc-lead\"\u003eThis is a 3.7V, 550mAh Li-Polymer replacement cell for the Nintendo DSi, NDSi, and NDSiL handheld consoles. It fits the original battery slot and connects via the factory connector without modification. OEM part numbers TWL-003 and C\/TWL-A-BP both cross to this cell.\u003c\/p\u003e\n\n  \u003cul class=\"bpw-desc-bullets\"\u003e\n    \u003cli\u003e\n\u003cstrong\u003eDSi, NDSi, and NDSiL compatibility:\u003c\/strong\u003e\n    All three models share the same battery bay dimensions, voltage rail, and connector pinout. The DSi's charge IC expects a 3.7V nominal Li-Polymer cell — this replacement matches that spec exactly, so the charge circuit behaves normally from the first session.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eBench tested on actual hardware:\u003c\/strong\u003e\n    We seated this cell in a DSi unit and cycled it through the console's onboard charge IC. The BMS accepted charge without flagging a fault, voltage at full charge measured 4.19V, and the fuel gauge updated correctly across the discharge curve.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eFuel gauge calibration on first install:\u003c\/strong\u003e\n    The DSi reads cell state by tracking coulombs from a known reference point. After swapping cells, run one complete play session to automatic shutoff before recharging — this lets the console's fuel gauge IC lock onto the new cell's actual empty voltage and recalibrate its capacity estimate accurately.\u003c\/li\u003e\n  \u003c\/ul\u003e\n\n  \u003chr class=\"bpw-desc-divider\"\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eDSi battery indicator jumping or showing wrong charge level after a cell swap\u003c\/h3\u003e\n\n  \u003cp class=\"bpw-desc-p\"\u003eThe DSi uses a simple coulomb-counting fuel gauge that references discharge data from the previous cell. When a new cell goes in, the IC has no baseline, so it interpolates — badly. The indicator can jump from three bars to one, or show full charge and then cut off unexpectedly. One complete discharge to automatic shutoff followed by a full charge resets the reference. After that cycle, the gauge tracks accurately against the new cell's actual 3.7V nominal curve.\u003c\/p\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eNew DSi battery lasting noticeably less than the original at first\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eFresh Li-Polymer cells ship with partial formation cycles — the electrolyte hasn't fully wetted all active material yet. On the first one to three cycles, usable capacity sits below the rated 550mAh. This is normal cell chemistry, not a fault. Capacity builds toward the rated figure over three to five full charge-discharge cycles. If capacity hasn't improved by cycle five, check that the battery contacts are clean and seating flush against the console's spring terminals.\u003c\/p\u003e\n\u003c\/div\u003e","brand":"BatteryWeb","offers":[{"title":"Warranty 1 Year","offer_id":43377550360666,"sku":"BWCS-TWL003SL-1","price":22.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 2 Year","offer_id":43377550393434,"sku":"BWCS-TWL003SL-2","price":25.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 3 Year","offer_id":43377550426202,"sku":"BWCS-TWL003SL-3","price":27.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0674\/4775\/0746\/files\/BW-CS-TWL003SL-1.webp?v=1778767310","url":"https:\/\/batteryweb.com\/products\/nintendo-dsi-replacement-battery-37v-550mah-li-polymer","provider":"BatteryWeb","version":"1.0","type":"link"}