{"product_id":"hp-550-replacement-battery-108v-4400mah-li-ion","title":"HP 550 Replacement Battery 10.8V 4400mAh 451085-141","description":"\u003cdiv class=\"bpw-desc\"\u003e\n  \u003ch2 class=\"bpw-desc-h2\"\u003eHP 550 \/ Business Notebook 6720s Series — 10.8V Li-ion Replacement Battery (451085-141)\u003c\/h2\u003e\n\n  \u003cp class=\"bpw-desc-lead\"\u003eThis is a 10.8V, 4400mAh (47.52Wh) Li-ion replacement battery for the HP Compaq 550 and HP Business Notebook 6720s family. It slots into the original battery bay and restores portable power to laptops running on dead or degraded cells. OEM part numbers 451085-141, HSTNN-IB51, HSTNN-XB51, and KU532AA all cross to this cell.\u003c\/p\u003e\n\n  \u003cul class=\"bpw-desc-bullets\"\u003e\n    \u003cli\u003e\n\u003cstrong\u003e550 and 6720s series compatibility:\u003c\/strong\u003e\n    These models share the same 10.8V battery rail, connector pinout, and BMS handshake protocol across the 550, 6720s, 6720s\/CT, and 6730s variants — one cell fits the full platform without firmware conflicts.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eBench tested on actual hardware:\u003c\/strong\u003e\n    We ran this cell through charge and load cycles on a 6720s unit. The BMS communicated correctly with the BIOS, accepted a full charge without cutoff errors, and reported capacity data over SMBus without fault flags.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eFirst-cycle calibration on HP 550 series:\u003c\/strong\u003e\n    After installation, run the laptop down to hibernate cutoff on battery only, then charge uninterrupted to 100% without interruption. This resets the BIOS battery learn cycle and clears the inaccurate health warning that routinely appears after a 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\"\u003eBIOS reporting battery health as poor immediately after installation\u003c\/h3\u003e\n\n  \u003cp class=\"bpw-desc-p\"\u003eThe HP 550 and 6720s BIOS reads cycle count and health data stored in the battery's EEPROM. A new cell ships with a blank or factory-default EEPROM state, which the BIOS interprets as an unknown or degraded battery. This is not a fault with the cell itself. Running one complete discharge-to-hibernate then a full uninterrupted charge allows the BIOS learn cycle to write fresh calibration data, and the health warning clears on its own after one to two full cycles.\u003c\/p\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eLaptop shutting down at 20–30% charge remaining\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 OS reads the old cell's discharge profile, misjudges the remaining capacity, and triggers a shutdown before the battery is genuinely depleted. It is not a faulty cell — it is a calibration mismatch. Run two full discharge-to-hibernate and charge-to-100% cycles without interruption to let the fuel gauge IC re-map the curve against the new chemistry. After two cycles, the reported percentage should track actual cell voltage to within a few percent.\u003c\/p\u003e\n\u003c\/div\u003e","brand":"BatteryWeb","offers":[{"title":"Warranty 1 Year","offer_id":43410809159770,"sku":"BWCS-HPF550NB-1","price":103.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 2 Year","offer_id":43410809192538,"sku":"BWCS-HPF550NB-2","price":117.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 3 Year","offer_id":43410809225306,"sku":"BWCS-HPF550NB-3","price":128.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0674\/4775\/0746\/files\/BW-CS-HPF550NB-1.webp?v=1779581158","url":"https:\/\/batteryweb.com\/products\/hp-550-replacement-battery-108v-4400mah-li-ion","provider":"BatteryWeb","version":"1.0","type":"link"}