Awanfi Batteery dead after a few month?

[whahooo 465]

Hello, 

 

i have a awanfi 3600 mah nimh battery that drives my Lunchbox only about 5 Minutes.

I discharged an charged the Battery a view Times.

It is fully charged after 45 minutes with 3 Amps....

 

I have a TBLE-02S and a Sporttuned Motor ibstalled.

I thought maybe it is a Brusheless or Liposetting or something with low voltage cut of.

Vut Tamiya do not support Lipos.

And if it would be in Brushless Mode it wouldnt drive at all....

[hIghQ 149]

While Tamiya ESCs don't support LVC for LiPos, they do so for LiFe batteries... so I'd still check for that setting.

[Willy iine 18805]

I run those exact batteries and no issue so far.  My NiMH sports packs usually last 6-7 years if not longer. 

Unlike NiCd, the trick is to keep a decent charge in them at all times.  For example if I know I can get four 12 min runs, I only run 3 and let them rest over night before charging them again.   Usually max charge I get in them at 3.6A charge rate is ~2500mAh and no more.  Any more means I discharged them too far which kills the weakest cells prematurely.  

Same goes for my 10+ year old NiMH which are 2000mAH, I know I can get near two 12min runs, I only run them once and let them rest overnight before recharge at 2A.  

[whahooo 465]

I always use the Dischargemode of my LRP Quadra Charger.

I thought you should discharge them as far as possible.......

[toyolien 4680]

4 minutes ago, whahooo said:

I always use the Dischargemode of my LRP Quadra Charger.

I thought you should discharge them as far as possible.......

I think it's only Nicads that need discharging.

[Willy iine 18805]

8 minutes ago, whahooo said:

I always use the Dischargemode of my LRP Quadra Charger.

I thought you should discharge them as far as possible.......

Unfortunately whoever said that probably confused NiMh and NiCd.  NiCd you do want to try to discharge to the min individually on a discharge tray, but sports packs are tricky as you can’t discharge individually.  This is why I still have side by side NiCd I made from 1997 that at in superb condition and no NiCd sport packs.  

NiMH’s selling point is that it holds no memory like NiCd so you can keep charge in them with no ill effects. 

[whahooo 465]

So there is no need of discharging them?

I can charge them even if they are 2/3 full??

 

If that is true, i will only drive  my cars until they are getting slow and  then i will charge them.

[Willy iine 18805]

43 minutes ago, whahooo said:

So there is no need of discharging them?

I can charge them even if they are 2/3 full??

 

If that is true, i will only drive  my cars until they are getting slow and  then i will charge them.

No need to discharge them.  Charging from 2/3 full is fine.  

You want to stop driving BEFORE your car slows down.  Slowing down (dump) means one or more of the weaker cells are near depletion.   

I always use a countdown timer off my radio to let me know when my time is up well before the cells start dump.  

[IoWBasher 170]

My understanding is that packs of multiple cells (Nicad and Nimh) should be trickle charged when new and every so often to balance the cells (maybe every 10th charge), otherwise you can get a cell that is either under or overcharged.

To the OP I'd suggest a good trickle charge to see if that brings back the capacity.

[Willy iine 18805]

Yes, trickle charging on occasion is a good way to balance the weaker cell(s).  

But if you follow the habit of not discharging too far you won’t need to do this either.   I don’t do it because trickle charging over charges the stronger cells which is also not good. 

Therefore, trickle charging is last ditch effort before recycling the battery for me. 

I mean do what is best for you.  I am just posting my experience.