Review on High Performance Replacement Battery CS03XL For HP Elitebook And ZBook Laptops - HSTNN-UB6S HSTNN-IB6Y 800231-141 800513-001 800231-1C1 CS03046XL P/N by Derek Jha

A little bit of time to replace but not hard. Nothing to do with the battery but the laptop design. When the laptop is so thin you need a screwdriver rather than just a few clicks to replace the battery.Remove the cover, a hand full of very small batteries, pop the connector and reverse with the new battery. Charge it up and laptop last a long time off charger.Well worth the cost and time to replace, and not very complicated.