If you are looking to power your Dyson with your Ryobi batteries, it can be done. The issue is the Ryobi battery shape doesn't really lend itself to using it on items that do not have provisions for the stub that sticks up. You would need a Ryobi battery adaptor and then a way to wire it to the battery connectors in the Dyson. One other thing to mention is Dyson uses a 6C battery configuration, while Ryobi and most other manufacturers of power tools use a 5C configuration. According to the interwebs, many people use their power tool batteries with good results, but I have never tried it personally.