I found a site that mentions that the EH5 (bolted) battery would have a capacity of 4.7Ah and EHW5 (welded) 5Ah.
I don't know how reliable this information is but it's interesting
www.ctechigroup.com
On this other site there are comparative graphs between EH5 vs EHW5
It would seem that the soldering batteries are a bit better than the others.
Maybe just a lower resistance inter cells due to welding
I don't know how reliable this information is but it's interesting

GS Yuasa HEV lithium battery production doubled

On this other site there are comparative graphs between EH5 vs EHW5
It would seem that the soldering batteries are a bit better than the others.
Maybe just a lower resistance inter cells due to welding