Lenovo IdeaPad S100 netbook won't turn on. What could be the problem?

Question

Do it yourself

I even bought a new battery for my netbook. Now the situation is this:

1. Without battery, plugged in - starts
   
2. With an old battery - does not start, the battery indicator is red
   
3. With an old battery, plugged into the outlet - it starts up every other time, the battery indicator lights up red. If you can wait for Ubuntu to load, it says either the battery charge is 1% or the battery is not detected
   
4. With a new battery - does not start, the battery indicator does not light up at all
   
5. With a new battery, plugged in - starts every time the battery indicator lights up white. If you can wait for Ubuntu to load, it says that the battery is charged
   

As an outlet, one could use it near the outlet without a battery at all, but the situation is complicated by the charger, which charges if you only hold it in a certain way at the netbook connector. You move a little - it stops charging and, accordingly, without a battery, the netbook turns off.
Maybe it's the contacts on the netbook, where the battery is inserted?

Answer 1

Here you yourself write that there is a problem with the charger. Well, check the charger cord for a break near the plug. There is a kink - buy a new charger or fix the kink.
If there is no break, replace the power socket in the laptop. They don't cost too much.
And of course, check the battery connector, it can be either dirty or torn off from the motherboard.
By the way, why in your scenarios there is no launch of a laptop without a charger with a new battery? I would like to see.