What? -> Lithium-thionyl chloride (Li-SOCl2)

I see, thank you for your reply.

I gave it a shot with some like the ones in the picture below but it doesn’t even power up.

I have five of the devices that take one battery each, if you consider that i need replacement every couple of months its an expense.

Were do you suggest to buy from in order to get the good quality originals.

Thanks

Manos