Ive replaced my TS22 internal lithium battery before and typically just soldered some new leads and placed the battery in the little compartment but this time I added a CR2032 holder which you can buy at Radio Shack for 99. cents. Now I can easily replace the battery in the future.

https://www.radioshack.com/product/index.jsp?productId=3060977&CAWELAID=162165418#

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