Starting in 2023, the IRS is offering a tax credit equivalent to 30% of the cost for battery storage technology. This credit, btw, goes all the way to 2033.
The only stipulations I have been able to find, thus far, is the capacity must be greater than 3kWh. Put into perspective, thats 3 - 12v 100aH batteries which can easily be had off amazon for under $800-900.
I have looked and looked and the ONLY qualifier is the 3kWh. No mention as to the battery technology (Lithium/AGM/etc). Oh, it does have to be put on a residence, but it does not have to be the primary residence and.... residence is defined as a place where you can live. They explicitly mention it could be a condo/house boat/apartment/single family home... so... pretty lenient on the application.
Form 5695 is the tax form. Line 5a.
Please add add'l info if you know more than this.