News:

C5alive filming with "oldgoldtech.com" at Brooklands Museum - 13th November 2010
http://c5alive.co.uk/forum/index.php?topic=1440.0


Author Topic: A different type of battery?  (Read 2905 times)

0 Members and 1 Guest are viewing this topic.

Offline rs20004wd

  • Newbie
  • Posts: 43
  • Battery level: 2
  • 4 legs may be better than 2 but 3 wheels better then anything!
A different type of battery?
« on: 16, September, 2012 - 20:47:37 »
Currently looking to upgrade the batteries for my C5 24V. Are these any good?

EBay description (Item number: 110867835984)

"Lithium Iron Phosphate, LiFePO4 is changing the face of battery technology.They offer high rates of discharge, long life cycles and are the safest lithium battery chemistry available.

Long cycle life up to 2000 recycles, 8 times that of lead acid battery, 3 times that of Ni-MH battery
Inherently safe, there's no danger even if the battery is misused
light weight upto 1/3 of lead acid battery, 2/3 of Ni-MH battery
Small volume of less than half of lead acid battery, smaller than Ni-MH battery
Low self-discharge, less than 5% after 6 months, good performance at high temperature, more than 70% capacitance remain after 1000 cycles at 45°C
It is environment friendly with no heavy metals or toxic material.
Dimensions:  L(mm) W(mm) H(mm) 181 76 167
Weight: 2.5 Kilo"

........although a great weight saving.

But the price is........£200........each!!!???

What do you all think?

classiccarman

  • Guest
Re: A different type of battery?
« Reply #1 on: 16, September, 2012 - 21:27:39 »
Do you have 2 x12 volt batteries and change them over when one is flat? I just wondered about the 24v tag on your C5.  I was thinking about making a 12volt lithium ion pack up  for experimenting with my C5's. I am lucky that I fix equipment in my job that uses 12 volt Lithium Ion packs of about 10 AH. These are made up of 8 x 3 volt cells but paired to make a 12 volt pack. Usually only one of the cells fails making the sealed pack useless and we have to fit a new pack and throw away the old (in the proper waste battery container of course ;)). I was thinking of splitting the packs open and using the good cells to make a high capacity pack which would be lighter than the original Lead Acid battery. They should be really suitable for the C5 as most of the new full size electric cars have battery packs made up of small L-Ion cells connected together.
You would need a charger capable of charging the L-Ion cells correctly. The packs also have built in protection as you can't flatten an L-Ion cell completly as this destroys it!

Offline rs20004wd

  • Newbie
  • Posts: 43
  • Battery level: 2
  • 4 legs may be better than 2 but 3 wheels better then anything!
Re: A different type of battery?
« Reply #2 on: 16, September, 2012 - 21:42:02 »
I run an Adam Harper Turbo Conversion 24V C5. I'm looking for a battery upgrade for reliability, longevity, weight reduction and to make use of the latest battery technology, but whilst keeping costs down too. As the current batteries may have seen better days, but still good, I need reliability as I use the C5 to commute to work. But £400 for the pair is not happening.
 When I get home they both get charged ready for next time. I use the latest Optimate charger.

Karl

  • Guest
Re: A different type of battery?
« Reply #3 on: 24, September, 2012 - 08:30:01 »
Nikki from the Battery Vehicle Society (BVS) converted a mini-el trike ,that normally uses lead acid batteries, to run on a lithium power pack.

Apart from the expense (around £2.5k :o) she found there were several other pros and cons. The lithium stuff did indeed give a massive improvement in range and also several performance improvements due to the massive weight loss when the lead batteries were ditched. Acceleration, top speed and hillclimb ability all increased very nicely.  However, the lithium pack needed a complex battery management system to ensure each individual cell was properly charged and balanced , and it also need the fitment of a heater system to help it work during cold weather.

Whether lithium is worth the expense on a c5 is open to debate and ultimately down to personal choice & circumstances. For me, the cheapness and simplicity of lead acid wins hands down mainly because I no longer use my c5's as much as before.

 

Offline KarlG

  • Hero Member
  • ****
  • Posts: 553
  • Battery level: 8
  • You don't have to be mad to own a C5, but it helps
Re: A different type of battery?
« Reply #4 on: 25, September, 2012 - 23:58:36 »
Hi BooBoo,

Quote
However, the lithium pack needed a complex battery management system to ensure each individual cell was properly charged and balanced

There are many types of lithium packs/cells, your quote is applicable to LiPos (or similar),  but with LiFePO4 no equalizers are necessary. A special charger is needed, otherwise can be treated the same as lead acids.

Do you know of a source for lead acid batteries that don't suffer from the cold?  :P

Quote
For me, the cheapness and simplicity of lead acid wins hands


I'll second that.

Cheers.

KarlG