I had printed a 3D trigger replacement (search on Thingiverse.com for various options/models) for a trigger but while reading I came across descriptions of connection issues with the battery pack inherent in the Dyson design. I had stored mine in a vertical stand and the weight of the battery, combined with the downward pressure from my hand when in use holding the grip, causes the battery pack to slip down within the handle sleeve assembly (battery, trigger, and handle assembly were all fine in my case, but was experiencing the Dyson sticking ON).
While I don’t have a elegant solution yet, simply adding a zip-tie around the battery to keep it in place and not “sagging” down slightly within the handle grip sleeve had fully resolved this issue from the OEM design fail for me and took seconds to execute for less than a penny. :)