Battery Voltage Range....Full to Empty

I guess you have the newest firmware. The old firmware lets the batteries to discharge to 105V until the battery telltale. However, when plugged in to recharge, the lowest charging voltage reports as 126V. Vectrix increased the lowest Voltage to protect the battery.

My highest cut-off voltage is also 147-148V, so it's ok on both counts :-)

152 or 153V cut-off is the highest the pack can have, but it's better for the battery life to be cut-off a little sooner. I think it cuts-off sooner based on the discharge capacity.

Toyota's claim to seemingly endless longevity to the Prius battery pack is the fact that the pack is never completely drained and never completely charged.

I have had some good experiences from NiMh batteries in the past, and also, lamentably, some bad ones too. Admittedly they have all been small in comparison to our huge packs, but still, they are NiMh.

One pack was in an electric toothbrush which lasted over 10 years of being charged many many times at a very low trickle charge, as is usual with that kind of thing.

Over ten years good service puzzles me, because of all the stuff I’ve read on “C” charge rates, which is best, and that really slow charge rates should be avoided etc. Anyway the pack in the toothbrush lasted all that time with no care from my part really, apart from just plonking it on the charger when the revs got a bit low and towards the end, it still was able to run at the same speed, but not for as long, just as you would expect.

The bad experiences were with AA packs, all charged with the very latest generation of intelligent chargers that monitored and charged each cell in its own “channel.”

One battery in the pack would sometimes drop off badly and drag the rest down until individually identified and replaced. I put that down to just a bad cell with a fault waiting to happen.

What concerns me is when our warranties expire. We will/could have a battery pack failure because of one bad cell which could be replaced without too much trouble or expense, if we could purchase the individual cells, identify the bad one, and replace it.

In this manner, over a period of time we would be on a “rolling” replacement program and keep the pack going indefinitely and not losing many potentially good cells.

I see the only thing on offer is complete replacement, or at best, one of the battery packs, at who knows what cost. £2,000 has been quoted for total replacement. What a bummer, if only one or a few of the 102 cells were to be at fault.

Hopefully with all the work Mik is doing, he will soon have some great experience in doing this kind replacement program.

Even more hopefully for the less technically minded amongst us, Vectrix will offer this service too. After all, you don’t change a whole engine because one part of it fails, and it is hardly a green exercise to toss away all those potentially good cells because of a partial failure.

I'm looking forward to news in the near future of the Lithium battery and the fuel cell hybrid which I've heard about. As it is, the current Ni-MH battery has more than enough range for my commuting needs, but should a newer technology become available in the future, it would be nice to know you could ride for longer and travel further before having to get juiced up.

Someday, we'll have benign nuclear batteries that will last the life of the owner, will be swappable from one worn out vehicle to a new rolling chasis and never ever need charging, and by the end of their useful life, they will have turned to harmless carbon dust. New vehicles will be sold without batteries (batteries sold seperately), and they will all be required by international law to accept the universal power pack. Then the world will be FUN! :-)

All it takes for a dream to come true is for somebody smarter than me to start thinking about it! :-)