1700ma bat. devided by the output of the charger(ma) = # hours

With the Piranha, you can charge at 200mah or at 5 amps, whatever the battery can take. Curiously, Venom-Racing says to charge my batteries at 3 amps, 5 amps for peak performance, I did that once and it became very hot! I charge them at 1 or 1.5 amps. I use a few of the Heng Long Batteries to power my airbrush and guns when testing. These are charged at .5 amps.

The Piranha will tell you how much juice is in the battery when its done charging but by that time my kids have pulled the wires out or knocked it over so I never get to see it!

By that formula, I get 4.25 hours for the wall charger. Not bad, actually, but not by any means swift.
I think I confused the initial charge time with what's recommended for the 1/6 M5 Stuart (12-14 hrs).

How long does it take to charge your packs at 1 to 1.5 amps, swathdiver?
Just wanting to know what kind of time savings I'd get with a serious charger such as yours.

-Harq

It's by no means a serious charger but it sure beats a wall charger. The fancy ones sell for over $100. It takes about 3 hours to charge a dead 3600mah battery set at 1 amp. Sometimes I've set them at 2 amps and am done in 45 minutes or so.

They say you shouldn't charge the batteries more then three times in a day and should wait 45 minutes before using after charging.

I just bought a Venom 7.2v 3600 mAH battery pack from Ebay. I noticed on the Venom-racing webiste that it says "DO NOT TRICKLE CHARGE BATTERIES." What does that mean?

I'm not sure myself. I think it means charging at a rate of less then 1 amp.

Found this on the net.

Jeff



"The idea of a trickle charger is that it can be left charging the battery continuously without fear of damage to the battery. To do this, the rate must be no more than 1/100th the power rating of the cell, and at least as high as the internal discharge rate of the cell. Most NiCd batteries will self discharge in about 3 months, or about 90 days. This means that the self discharge rate is about one percent per day, so we see that the "rule-of-thumb" 1/100th trickle charge rate was designed to offset the self discharge rate of NiCd batteries. This rule is used for all rechargeable batteries that I am familiar with. (I am not yet familiar with the newer rechargeable Alkaline batteries.) So, we need to design a recharger that can supply no more than 1/100th the current rating of the battery we wish to trickle charge. An important point is that neither liquid or gel cell lead acid batteries have this high a self discharge rate, and in fact some well designed NiCds don't either."

a trickabout batteries, so you wont forget :
nicad=nicrap
nimh=mmm ,good

Could you explain that? I mean let's be more constructive about it by fleshing out why NiCd batteries are "nicrap" and NiMH are mmm, mmm, good.

I think it depends on the application. Since NiCd batteries have lower internal resistance, they are still preferable in very high current drain uses such as powering cordless tools and RC cars. NiMH batteries perform better with low to moderate drain devices like digital cameras...
NiMH batteries have more capacity than a comparatively sized NiCd battery and have little to no memory effect too. That's about all I can think of.

-Harq

harq.<<<my previous post was for beginners who dont know what to check when purchasing a battery in a store, NIMHs are much more expensive ,can be fooled buy the seller.
i agree with you

in the desert , i would take a nicad(it still have some low juice!).
but low juice is no good with rc tank.cant move but i could spin turret and machine gun for another hour=nicrap.

nicrap have memory effect (takes knowledge, time and patience).

i cosider an rc tank as a medium drain rate compared to a drill or other 7.2 v racing car.

nimh are more trouble-free ,more constant voltage the drops faster,
can be fast-charged just for a demo of your tank to friend.
happens often with an airsoft tank.

the only thing i dont know is wich one last longer in years? (not playing time)
i would probably bet on the nicrap.[&:]

That sounds great. I am just trying to learn more about them as I've used only NiCads for years. I guess I was wanting you to tell me that RC tanks were in fact a low/med current drain vehicle but I wasn't sure. Seems like the tank could be a high current drain device because of all the functions (turret traverse, gun elevation, sounds) however.

Had not priced NiMH before so it is surprising to note they are less expensive than NiCd.

Are you saying they have more constant voltage but it drops faster than a NiCd??


Thanks for the info,
-Harq

sorry , made a mistake ,nicd are cheaper then nimh .[&o]
will correct my last post.
yes nimhs ,when they drop ,they drop fast.