Already since 02/01/2021 it is forbidden in the EU to sell battery acid with a concentration limit above 15 percent to end-users or non-commercial consumers.
The new EU regulation is intended to prevent battery acid from being misused for bomb-making. Sales are now only permitted to commercial customers. So in the future, mechanics will have to use maintenance-free, gel, lithium or similar batteries. Otherwise one must go to a workshop to fill the battery.
Stocks, which one has already at home, may be consumed still up to 01/01/2022, after that also the possession is illegal. However, this does not apply to the battery acid used in the batteries, here, of course, the possession remains legal.