Hi John,
there's a couple of factors that must be taken into consideration. Do you have the original Sinclair battery top and wish to retain it, or do you have normal battery connectors?
If you have the original battery top,then you need a type 063 battery, but then you also need terminal adaptors.
If you have normal battery connectors, then most medium sized batteries will fit, but take care with the height. Leisure batteries are recommended as deep discharging a car battery can lead to damage.
There is a post in the forum discussing batteries, and I recommend that you read it.
http://www.c5owners.com/sinclair-c5-forum/topic/592/which-battery-is-best
Av phun.
Karl.
posted on: 03/07/2015 19:20:23