With some models of HP laptops, including those that I have, the power connector has a skinny center pin that is used to communicate between the charger and the bios. That pin is very fragile and if it breaks off then the bios will refuse to allow battery charging. This leads to a stone dead battery and no way to recover. And in many laptops the fragile solder connection of the power connector to the motherboard will break and no charging at all, but the computer will work if the battery can be charged in another computer. Re soldering would not be hard but the 23 pages of instructions for dis-assembly discouraged me.
I have been wondering about opening the battery pack and instead of replacing the cells, add connections to run it from external DC power, such as 12 volts in my car. Then I could use the free WiFi at fast food places from my car and not need to stay inside and run on battery power because of no AC outlets available. Regulating 12 volts down to 10.73 volts should not be so very hard, I don't think.
I have been wondering about opening the battery pack and instead of replacing the cells, add connections to run it from external DC power, such as 12 volts in my car. Then I could use the free WiFi at fast food places from my car and not need to stay inside and run on battery power because of no AC outlets available. Regulating 12 volts down to 10.73 volts should not be so very hard, I don't think.