Confirm which model of Dyson vacuum you have (like for me I have a V8 model) and find the battery adapter that matches. Like if you have a V6 and want to use your Bauer batteries, lookup something like "Dyson V6 battery adapter for Bauer batteries" - seeing as Bauer batteries are Harbor Freight's version of someone else's battery, you might need to do some digging to make sure you get the right one.

It's like 3 screws to take the OEM battery out, you put the battery adapter in its place (using the same 3 screws), and then slide the battery on and off just like your other cordless tools. It's pretty awesome.

A little off topic but the thing with tools is that once you buy into their ecosystem they think they have you... Ie. Bauer, dewalt, Makita etc. Because the batteries only work with that brand...

But a couple years ago you could start being able to buy adapters on ebay/Amazon (about $15 each) and it changed my world. I had upgraded to Makita from Ryobi for most things but still had some old Ryobi tools that were perfectly fine even tho their batteries had long since died. Bought a few adapters and now use my long lasting Makita batteries with them no problem

This has opened up my world as well since now I buy any brand tool I want or need if I see a good deal or prefer another brands model (Milwaukee, dewalt etc) and just buy an adapter for my Makita battery!