I am wanting to buy a circular saw that is compatible with Worx 20v lithium ion batteries I already use… Do these batteries work with Black & Decker’s 20volt Li-ion saw? Or any other brand?
Unfortunately your pretty much going to have to switch battery platforms to get into a cordless saw. While it is technically possible to modify some tools to work with different batteries I think Worx to X brand would be quite a significant undertaking and probably cost prohibitive.
I have modded very successfully Black and Decker batteries to Porter Cable and vice versa. It’s quite easy to do and they are both made by Stanley Black and Decker.
I think your assessment is absolutely correct.
The only tool battery adapters that I recall having seen are this one from Dewalt "
That helps some older Dewalt tools work with newer Dealt batteries.
and one from a third-party vendor for Makita:
or this one
The veracity of what you say is also supported by the lack (as far as I know) of 3rd party vendors selling adapters to let you plug Brand X batteries into Brand Y tools. I suppose that if it were remotely easy someone would be doing it.
Stuart had a discussion about this last year - and I don’t think much has changed
Here are some previous discussions:
20v black and Decker charger on a 24v cobalt battery