new batterys please advise

[beason]

new batterys please advise on maintanace

I recently bought 2 brand new stick packs for my e-maxx project. I went with the venom 6-cell 3000mah nimh packs.

I have the Duratrax intellipeak ac/dc charger.

it will trickle charge, peak charge from 0.5 to 6.5 amps, discharge at 1 amp with a cut off of 2.6v, and discharge/recharge cycle.

Now my question is, what is the best way to maintain these? I've never had brand new batterys and at $25 a peice i want them to last awhile...

Should i discharge/charge cycle them? how many times? what amps should i charge at? I'm supposed to store them with a little charge on the right?

:bowhhh electric gawds please bless me with your knowledge!:bow:

 

[Rolex]

Hopefully SweetDiesel will back me up on this, but with NiMH you can NOT charge above their capacity like you can with NiCads. You must charge at their rating.
For a first time charge, you charge them at half their MaH, and after that just charge at their normal rate. They do not have to be cycled like NiCads since they do not have 'memory'.

 

[beason]

what is the normal rate?

 

[Rolex]

Normal means charging a 1500 AT 1500 or a 3000 at 3000.
With NiCads, you can charge a 1500 at 3000, or double their rating.
I also think that trickle charging is not good for NiMH or LiPos, but I'm waiting for SD's input on this.

 

[beason]

i can't set a cutoff mah, just the rate it charges at in amps. so your saying charge the 3000mah pack at 3amps?

 

[Rolex]

That's the going rule for NiMH batts, but I THINK it's also advised to give them their first charge at 1/2 that. Wait for SDs word on that.

 

[sweetdiesel]

The safe route is to first charge at half the rated capacity (1.5 amps) for the first charge to help condition the pack. After that charge at 3 amps. Make sure your delta voltage cutoff is set to 5mv per cell, and monitor the pack temps. If the charger cuts off at 115-120 F you're fine, any lower and you're getting a false peak. Any higher than 130 F and you're in the land of overcharging. Adjust your delta V accordingly.

To cycle a nimh stick pack, discharge to .9 volts per cell or 5.4 volts total. Trickle charge will not hurt the pack but nimh perform best right after a high amp peak charge. Try not to run more than 2 charge cycles per day to maximize cell longevity.

You'll find that with your nimh packs final charged voltage will be higher than the label voltage, and mah will also be higher. Keep track of how many mah you are getting back into the pack. With a little care, you should be able to get 25-30 charge cycles before the pack begins to deteriorate.

Depending on the brand, some high quality race packs can take more than a 1C charge. Each manufacturer will have their own maximum charging specifications.