Here are the parts for the battery balancer.
They are all available from http://www.rockby.com.au
For the 50 batteries, there are:
· 100 x 5mm Terminals
· 100 x 6.8v 5W Zener Diodes
· 50 x 4.7R 1W resistors.
I will make up a jig to assist soldering them all quickly and accurately.
After completion they will be encased in heat-shrink.