TOPIC:

Do i need one of these for NiMH batterys?

and wot are they for/wot benefit do they have on the battery?

www.modelsport....ucts/30039

jtf

They're probably most useful on NiCads. But conditiong seems to help the life of NiMHs too.
I wouldn't say that you'd really need one.
Most likely the charger of your choice will also have a discharge function...

excellent,thanks again Edou.

hopefully i can start my boomer resto soon

jtf

oh yeah,forgot to ask..wot is conditioning.wot does it do?

sorry for being a bit thick about this i just wanted to get it all straight in my head so i know wot im doing.

jon_the_fox wrote:

wot is conditioning.wot does it do?

Conditiong is a cycle of loads and discharges.
With NiCad you can prevent the memory effect with this. Or (partially) get rid of it.
If you do not fully unload this kind of battery and start loading it, you will have less capacity (power storage) remaining.
But NiMHs seem to also live longer when using this procedure once in a while, although they have no memory effect.
I'd recommend not storing NiMHs empty for long periods of time btw. That seems to kill them off.

so in essence to condition a NiMH battery i would....

charge
discharge

just once or would i have to charge discharge several times?

With Nicads, charge it, run it, then after running discharge it. I always make sure they're discharged before I charge them. To discharge, I use a car headlamp bulb, but any meaty resistor will do it, Don't use to low a resistance value (Ohms) or the battery will get hot, possibly damaging it.
Don't know if you need to do it with NimH though, never had one last long enough to charge it a second time....

eddrick wrote:

With Nicads, charge it, run it, then after running discharge it.

thanks eddrick,im considering getting a NiCAD battery too,where is the best place to get a good quality battey from?

then il have both and i can see which one i get on with the best.

I'd just charge it & use it until the car begins to slow down, then let it cool down & recharge it whether you're going to run it again or store it. NiMH packs loose charge all by themselves, once they go flat they may be no more good - so giving them a charge every so often when you're not using them is a good thing

You should see an improvement in run times after half a dozen charge/run cycles - but I wouldn't go to the bother of doing it on the bench.

just once or would i have to charge discharge several times?

Since you'll be using NiMH, I'd recommend 2-3 cycles every few months.
That'll keep 'em from dying too...
Depending on the quality of the cells, you might want to be careful with an uncontrolled discharge.
Best would be to stop discharging your packs at about 0.8-0.9V, so 4.8-5.4V for the whole pack.

As far as I know, your only options for nicads at the mo are second hand (Tamiya ones are usually ok, but some might need scaring back to life) or build your own from power tool packs. Although nicads are coming back to the power tool world, I think it's unlikely they'll come back to toy cars as LiPos appear to be so fantastic.
& like Jonny said, let the battery cool before recharging it (You'll find they get quite warm with aggressive driving, & deep discharging). A cool battery has a lower internal resistance, so will charge happily at a higher rate & the final 'charged' voltage will also be higher