Resource required for creating a super cap 12v battery

Can someone help with a resource for creating a 12v battery from supercap as their capacity drops quickly when one chains them to make 12v . I also want to know if I need to use NiMH to act as a portable battery that I can use to charge storage batteries, instead of supercaps. I have a 6kw generator and I have rack sla batteries and I need something that take a charge faster than the battery. I would like to know where to buy large supercaps.

Hi Richard,

This one is a bit out of my league, perhaps someone else might be able to drop in and help.

With that said, I’ve seen lots of DIY Tesla Powerwall’s built from banks of LiPo 18650 batteries. They have a fast charge/discharge, although not much of it is straightforward.

NiMH has more power limitations than LiPo. Unsure if it would affect your project requirements though.