I started my battery tools with DeWalt back in the 12v days. At that time, the brands that seemed to be trustworthy were Makita, Milwaukee, and Dewalt. Ryobis at that time didn't seem to last long, (not just batteries, but the tools themselves wore out). The newer ones seem to be good tools, but no need to change battery types.. The Milwaukees were good but didn't fit my wide but short fingered hands. Makita was more expensive, so it was DeWalt. Have stayed with them and haven't had reason to change. The 12v still work, but the batteries are toast and no reason to try and rebuild them. My 18v are still running strong, although I have upgraded to the 20v lithium with my impact driver. I have made it a practice to buy batteries during DeWalt's January sales, so haven't had to break the bank.
I also have corded tools. DeWalt miter saw and ROS. Ridgid TS and shop vac. Fenn multi-tool. Porter cable and Craftsmen circular saws, Hitachi floor standing drill press. Craftsman and unknown brand (one is over 50 years old) drills, as well as a Porter Cable pneumatic framing nailer. I think all my Black & Decker tools have long since worn out.