I recently purchased two battery's for different dell laptops. One laptop has a flashing red battery sensor light on the laptop. It keeps appearing but with the old battery it did not appear. I don't know what this means. this laptop is a Dell XPS M148 The other laptop was working fine and then one day it did not detect the ac adapter so it would not charge. Then we believed that the battery had died because every time I unplugged the charger the laptop would instantly turn off. So I bought a new battery hoping that was the problem but it wasn't. The laptop still wont charge and every day the battery percent keeps decreasing. My dad thinks that the charge card is the problem, and it is the reason why the laptop won't charge. I'm not sure what is though and what I should do. This laptop is a Dell inspiron 9300 I bought both batteries from amadvance.com I bought a different battery from them for a different laptop a year ago and that laptop works fine.