Tuning cheap key solar LED-lights (3V cr2032)

Is this correct ?(I added 2pcs silicon wire to the switch to connect 2pcs solar LED-keyrings 3V.)

+ How to add a bigger battery what is the battery's max voltage ?

 

It looks like you are trying to pair two units together. As the original design is a crude lash-up of a device to begin with you are just compounding any potential problems; this circuit needs lots of things to be equal to work.

 

As a single unit "Solar Keyring LED Torch" they look like this: (How to connect two(2+) or more of these together ?)

 

I'm confused by your question;
Did you mean how to operate two of these keyrings with only one switch?

If so, you can just modify both to use common ground, then just switch the positive side.

Bigger battery?
Why not two AA cells? Both combined would yield 3V.