High Power Nimh Packs?

[Gruntfuggly 562]

There are some high capacity nimh packs available on eBay recently - 5300, etc.

Has anybody used them - are they actually any good or are they a scam?

And before anyone says "Don't bother - use LiPo instead" - I don't run often enough to justify a new charger and packs...

[hedge 314]

There are some high capacity nimh packs available on eBay recently - 5300, etc.

Has anybody used them - are they actually any good or are they a scam?

And before anyone says "Don't bother - use LiPo instead" - I don't run often enough to justify a new charger and packs...

They should be fine. NiHms have been getting larger and safer.

Cheers

Paul

[bigoggy 203]

i run 4600 and 4700 nimh, and they are great.

i can get upto 4 hours run time from one in my pajero

[Gruntfuggly 562]

Cheers guys - sounds like I might have to try one out...

[lucasan 28]

I looked for 5300 mah nimh on ebay but didn't see any. Is there a brand I can search by?

[Gruntfuggly 562]

Try searching for "5300mah"...

I've just spotted some 6800mah too!???!

[Singapore_959 18]

Packs like these are heavy. I only have one pack above 4300 and I will never buy a pack above 3900 again.

The only thing these give you is longer run times. But the car is much heavier with such packs, so the result is more strain on the motor. All they really achieve is hot motors due to longer run time and heavier weight car to move around.

[lee172 0]

i'd stick to a brand name, my fave's are Orion and GP cells, not only do they take in more than there quote mah, they provide brilliant punch as well.

i have bought cheap packs in the past and they have little punch, low runtimes and within a few months they are pretty much dead.

[Origineelreclamebord 45]

What I've been told about the high power NiMh packs is that they can in some cases be(come) unstable and explode (if they are not balanced I believe, but that has to be confirmed). The higher capacity cells don't hold their charges as well as lower capacity ones either I heard.

Terry.Sc commented on this that the NiMh technology has been pushed to it's limits because it has a lower internal resistance than LiPo (and as such was for a while preferred by racers) -

So apparently, in the aim for more capacity, compromises were made on safety

http://www.tamiyaclub.com/forum/index.php?...ttery&st=20

Here is the link of a topic that I started quite a while ago It should include the information I mentioned above

[TheBlueDragon 0]

I've only seen a battry pack explode when it got too hot nd overcharged. I used to get my batteries from cheapbatterypacks.com where you can design your own battery and I've always used GP battery packs, never had one go wrong on me yet

[Origineelreclamebord 45]

I've only seen a battry pack explode when it got too hot nd overcharged. I used to get my batteries from cheapbatterypacks.com where you can design your own battery and I've always used GP battery packs, never had one go wrong on me yet

Individual cells can charge and discharge unequal without a balancer (which the NiMh batteries normally lack from what I know) - When charged and discharged over time, the difference can get bigger, and one or several of these cells can get overcharged.

This doesn't have a lot to do with the manufacturer - in the end there is a threshold, and if it's reached, it will blow. However, this rarely seems to happen, and batteries of better brands would probably have more tolerances before they reach this threshold (although high capacity cells are known to have a lower tolerance in general).

[bugjammer 2]

For the racers amongst us, this is the ONLY place to get NiMh cells

http://www.dpmodelracing.com/

They are matched on peak voltage and internal resistance - just right for our short races we have here in the UK

Darren and Dale who run DP both race 1/12 oval and Darren is a Cometrc.com sponsored touring car driver - he also won last years Tamiya Eurocup in the stock class with 5 tq and 5 wins, whilst developing the Team Magic E4RS touring car - busy bee indeed!