DeWalt built a battery that changes voltage when you move it between tools

I have two battery fleets in my garage. Ryobi 18V packs run my drill and the impact driver, and my Ryobi 40V packs run the trimmer and the blower. Neither one fits the other's tools. That split is normal across cordless brands, and it's a big part of why the battery is the real business for all of them.