Best Traction lead acids?

[aminorjourney]

So I'm interested to find out what people's best lead acids are for traction.

If you reply please include why you think they're great, the cost and power etc etc

Nikki.

[ChrisB]

My personal faves have to be Chloride's old tubular range, think its exides tubular range now.

Or Trojans range of traction units

I have had experiences of both, and they seem to be able to withstand loads of grief and still manage to deliver the goods regardless.
Its tricky to include power and costs as I've experienced several different ranges of these batteries and these of course have different powers and different costs.

I think at the end of the day, if you want reliablity you have to suffer weight and expence.

ChrisB

[aminorjourney]

Yes, I think that is the realisation I've come to!

I've been speaking to John lilly and he thinks there may be some highish losses on my car connected with the wheels - so we'll need to fix those up as well. (I didn't know friction losses could be as high as 1kW!)

I'll keep everyone posted and just hope my range increases for the summer!

[EVguru]

The tubular plate Oldham 3KQ11 used to be the recommended 6 volt unit for the Enfield.

Some poeple had very good range and life. I've heard of sets lasting over 10 years.

However, if you live in a hilly area, you should use flat plate batteries, because the tubular plate batteries have a short life if you draw too much current.

I like to design vehicles so that even with a discharged battery you can still achieve the desired cruise speed. If the voltage needed to achieve cruise speed is close to the nominal pack voltage performance can fall off fast. The Enfield for example has no voltage to 'spare'.

Tubular plate batteries have a relativly high internal resistance and will sag quite a lot under load, like climbing a hill. If you have 'spare' voltage it's not too much of a problem, but otherwise as the voltage drops you slow down. If you 'need' to maintain speed, you now try to use more throttle and the batteries are likely to sag a bit more, so you end up in a circle of ever increasing currents.

It takes the same amount of energy to drive a car up a hill, no matter how long it takes (same with acceleration). Twice the speed (power) equals half the time. In the real world, with lead acid batteries in particular, the usable capacity goes down with increased discharge.

[aminorjourney]

Hi Paul,

Well, riddle me this:

I'm using a City El running at 36v nominal. It's restricted to 125A max current draw, so about 4.5 kW maximum - although the motor is of course rated continuously at a much lower 2.5 kW.

What cells would you recommend for good range and power? I am having issues with the current pack and even though the voltage drop off was marked last night (with only 14 miles on the clock) it only put 1 kWH into the batteries on charge.

I'm contemplating Lithium, but I know that not everyone is a fan of them

[ChrisB]

Its interesting you say it only put back in 1Kw , is your charge a fully automatic thingy ?? I cant remeber.

I've personally always found so called "fully automatic" chargers to not be as "fully" as they say and tend to er on the light side of the charge.

Whats your veiw also Paul ??

ChrisB

[Peter Eggleston]

Hi
For three years now I have been running my truck on lead gel batteries as used by British Telecom as backup power for transmission stations and they are still getting better. These can be bought on ebay for very little money. I have paid as little as £ 11.00 for a 40 kg battery. They may be new or have had very little use as they are only used for emergency supply in the event of a power cut, but BT replace them regularly so they know they are always good.
In comparison before this I tried a pack of Elecsol leisure batteries, the really big expensive ones. They hardly lasted one year and performed very badly.
Brand names of these lead gel batteries include Sonenshine, Powersafe, or GNB Marathon.
There are usually some listed on ebay under lead gel or leisure batteries and the suppliers usually have any number and in different sizes.
Peter