I'm not doubting they are an excellent way to power a C5, but for me it's all down to basic economics
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As an example those old Drivemaster lead/acid type 063 batteries I obtained in May 2007 were left over from the London/Brighton run. At the time they cost about £30 each and have been used to power my C5's on every meeting since then , as well as other events like the gadget show at Bruntingthorpe etc. I've charged them using either converted Sinclair chargers, or a standard Halfords car battery charger. Nothing special, or expensive , required. They've now died but I feel I've had my monies worth
If I had loads of cash to spare then yes, I would be first in the queue for lithium, but until then I'll stick to car batteries
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