Thank s Paul,
i have already seen this Swedish company. Very interesting in the DIY Winston Thundersky cell assembly. They will balance the cells before delivery that are from the same batch. Looks like a more cost efficient alternative to Lithionics.
The website is more in Swedish than English.
They have to 24v 400Ah cell packs One with 8 cells the other with 16 cells not as tall.
one interesting features seems to be in case one prismatic cells fail apparently they can be exchanged at moderate cost and the whole setup can be rebalanced. Maybe more useful than a theoretical 10 year guarantee.
progressing towards the truth of lithium and following Oliver of Nautica Vela who has engineering skills I lack.