{"product_id":"benq-joybook-r55-replacement-battery-111v-4400mah-li-ion","title":"BenQ Joybook R55 11.1V Replacement Battery 2C.201S0.001","description":"\u003cdiv class=\"bpw-desc\"\u003e\n  \u003ch2 class=\"bpw-desc-h2\"\u003eBenQ Joybook R55 — 11.1V Li-ion Replacement Battery (2C.201S0.001)\u003c\/h2\u003e\n\n  \u003cp class=\"bpw-desc-lead\"\u003eThis is an 11.1V, 4400mAh Li-ion battery for the BenQ Joybook R55 notebook. It replaces OEM part number 2C.201S0.001 directly. Capacity is 48.84Wh — matching original spec.\u003c\/p\u003e\n\n  \u003cul class=\"bpw-desc-bullets\"\u003e\n    \u003cli\u003e\n\u003cstrong\u003eJoybook R55 fitment:\u003c\/strong\u003e\n    The R55 uses an 11.1V three-cell-series pack with a proprietary connector and a BMS that handshakes with the BIOS over SMBus. Any replacement must match the voltage rail and carry the correct EEPROM identifiers — otherwise the BIOS flags the pack as unrecognised and blocks charging.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eBench tested on actual hardware:\u003c\/strong\u003e\n    We cycled this cell through full charge and discharge on an R55 chassis. The BMS communicated correctly over SMBus, the BIOS accepted the pack without a health warning, and charge current stepped down normally at the 80% threshold before topping off.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eFirst-cycle reset on the R55:\u003c\/strong\u003e\n    After installing, let the laptop discharge fully to hibernate cutoff — do not interrupt it. Then charge straight to 100% without unplugging. This forces the BIOS battery learn cycle to reset against the new cell data and clears the inaccurate health flag that appears after every cell swap on this platform.\u003c\/li\u003e\n  \u003c\/ul\u003e\n\n  \u003chr class=\"bpw-desc-divider\"\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eWhy the Joybook R55 BIOS reports poor battery health after a cell swap\u003c\/h3\u003e\n\n  \u003cp class=\"bpw-desc-p\"\u003eThe R55 BIOS stores learned capacity data from the previous cell in non-volatile memory. When a new pack is installed, the BIOS compares live readings against that stale dataset and logs a mismatch as poor health. This is not a fault with the replacement cell — it is a calibration lag. Running one full discharge-to-hibernate followed by an uninterrupted charge to 100% rewrites the BIOS learn table against the new cell. After two or three cycles the health indicator normalises.\u003c\/p\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eJoybook R55 shutting down at 20–30% charge shown on screen\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eThis happens when the fuel gauge IC has not yet calibrated against the new cell's actual voltage curve. The IC maps the old cell's voltage cliff onto the new pack, so it calls empty too early. The fix is the same learn cycle — discharge to hibernate cutoff, then charge uninterrupted to 100%. Repeat this two full cycles. After calibration the OS fuel gauge aligns with real cell voltage, and the laptop will not cut off until the cell actually drops below the BMS low-voltage threshold of approximately 9.0V under load.\u003c\/p\u003e\n\u003c\/div\u003e","brand":"BatteryWeb","offers":[{"title":"Warranty 1 Year","offer_id":43410849071194,"sku":"BWCS-AUF3NB-1","price":73.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 2 Year","offer_id":43410849103962,"sku":"BWCS-AUF3NB-2","price":86.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 3 Year","offer_id":43410849136730,"sku":"BWCS-AUF3NB-3","price":95.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0674\/4775\/0746\/files\/BW-CS-AUF3NB-1.webp?v=1779581357","url":"https:\/\/batteryweb.com\/products\/benq-joybook-r55-replacement-battery-111v-4400mah-li-ion","provider":"BatteryWeb","version":"1.0","type":"link"}