Amazon.com: AC Doctor INC Laptop Battery for HP EliteBook 6930p 8440p 8440w Compaq 6530b 6535b 6730b 6735b ProBook 6440b 6450b 6540b 6550b, 5200mAh/11.1V/6 Cell : Electronics
Synergy Digital Laptop Battery, Compatible with HP Compaq 6730b Laptop, (Li-ion, 10.8V, 6600mAh) Ultra High Capacity, Replacement for HP 484786-001, 491173-543, HSTNN-144C-A, HSTNN-144C-B Battery - Walmart.com
Laptop Battery for HP Compaq 6730b | Probook, Laptop battery, Laptop battery life
HP 6730B Battery
6 Cell Battery for HP Compaq 6530B 6730b 6735b EliteBook 6930P 8440P 8440W 6540b | eBay