Traveling with Eurowings with an electric wheelchair

This will be a long post, so i'm sorry in advance.
I have a trip to Hamburg planned for the end of August, it will be a solo trip and my first outside my own country so i'm quite excited for it. As per title, i'm traveling with Eurowings (although on the inbound flight there will be a layover in Zurich and i'll board a plane operated by Edelweiss Air instead). I'll be traveling on my Progeo Exelle Vario, outfitted with an AAT Alber Solo conversion kit to make it electric. My worry about this flight is mainly related to the battery, which is a lead-gel one: i have traveled already in the past with this and i know lead-gel batteries are fairly accepted with little restrictions, but another problem that comes with it is related to transport. In case someone doesn't know this Alber Solo, the battery is stored in a bag right underneath the wheelchair and is designed to technically be detached from the cables and taken off in some cases, but being a lead-gel battery, it weights around 10kg, which for me is increadibly heavy. On Eurowings's site, it says that if the battery is designed to be removed, it must be taken off the wheelchair and carried in the plane hold "inside a solid package". Not knowing extractly what they ment with that, in previous plane travels with Ryanair, which also have this ruling, i ended up putting the battery into my checked baggage inside a smalled, rigid bag with "Non Spillable Battery" written on it, and somehow that was semi-accepted, even though it was obviously a bit of a nuisance because i had to move in the airport in manual mode without the comfort of pushing the stick of the joystick, so now that i have another flight with a different company, i'm wondering... was that really the way to do it ? With this rule, do they actually mean you have to get to the airport with the battery of your wheelchair already removed and stored away ? Or is a ruling ment mostly for the airport and the plane's crew on how to handle the trasport, as in i have to do nothing of that and they will deal with removing and storing the battery themselves ? The document for the air trasport of the battery also mentions that it "MUST be removed and trasported in the plane's hold as a checked baggage", i want to understand if i misunderstood the meaning of that rule or not, so if anyone has any experience with this and has a response to give, i thank you in advance.