Replacement battery is made with high quality battery cells, 100% compatible with laptop. Batteries are meet or exceed the original equipment manufacturer specifications (voltage, capacity, safety and compatibility), all of them have passed international certification( CE, UL, ROHS, etc.), Strict quality and safety testing( QA & QC) before leaving the manufacturer. And the battery shell was made of high quality environmentally friendly and fire-resistant materials. These batteries also have internal circuit boards with smart chips, which allows the battery to communicate with the laptop to monitor battery temperature, performance and output voltage. Note:- battery must be fully charged with over 8-12 hours for the first time use, first 3 charge/discharge cycles are very important to get actual performance. In case of battery not getting charged you must check adapter's output it should be same on multimeter as laptop input power. Don't consider the battery is faulty, it may be fault in other parts of laptop also.