Model Boat Mayhem

Please login or register.

Login with username, password and session length.
Pages: [1]   Go Down

Author Topic: charging nimh packs  (Read 3794 times)

martno1fan

  • Full Mayhemer
  • *****
  • Offline Offline
  • Posts: 2,472
  • Location: Blackpool
charging nimh packs
« on: January 19, 2007, 12:56:13 pm »

hi i have a new 7.2 volt 3,300 nimh pack is it ok to use my standard nicad charger to charge it? its a 250ma charger thanks!!
Logged

Sub driver

  • Full Mayhemer
  • *****
  • Offline Offline
  • Posts: 612
Re: charging nimh packs
« Reply #1 on: January 19, 2007, 06:50:24 pm »


  :)  Hello. from what I understand you should avoid using a FAST, PEAK Nicad charger on NIMH cells....something to do with the PEAK charge that it puts into a cell etc, I understand you can SLOW charge them BUT I would buy a NIMH charger as most of them can do both NIMH and NICAD these days, there not expensive.

I have a PROTECH multi charger 6 it does NICAD, NIMH and gells from 1.2v to 12v , 0.27- 7 amps.... you can even use all 6 chargeing sockets at the same time from 50mah up to 500mah.  Treat yourself  ;D ;D ;D

Hope this is of use, No doubt some expert will be able to tell you more  ;)
Logged

Bridkid

  • Full Mayhemer
  • *****
  • Offline Offline
  • Posts: 191
  • Location: Sunny Bridlington
    • Bridlington Model Boat Society
Re: charging nimh packs
« Reply #2 on: January 19, 2007, 07:31:01 pm »

Best thing to do is slow charge for the first time at 100 Milliamps and then fast charge after the first run. I usually slow charge about every 10 or so runs as this re-balances the cells......so I'm told. Quite right, don't use a traditional Nicad charger, there are plenty of reasonably priced chargers on the market that will do the job.
Try this link    http://www.alshobbies.com/shop/cat.php?id=51&Desc=

Cheers,
Ian.
 8)
Logged

Fast Electricals

  • Full Mayhemer
  • *****
  • Offline Offline
  • Posts: 95
  • Location: Orpington, Kent
Re: charging nimh packs
« Reply #3 on: January 19, 2007, 11:01:30 pm »

Most fast chargers detect the end of the charge by monitoring the battery voltage to detect when the voltage "peaks". On a NiMH battery the peak is less pronounced than on a NiCd, so you will need to use a fast charger designed for NiMH cells.

Neil

martno1fan

  • Full Mayhemer
  • *****
  • Offline Offline
  • Posts: 2,472
  • Location: Blackpool
Re: charging nimh packs
« Reply #4 on: January 20, 2007, 09:29:56 am »

thanks guys i used the slow charger for my nicads at 250 mah and it worked a treat after 12 hrs the battery was nice and warm not hot so ill give her a go on sunday weather permitting after a quick boost in the morning.as its not a peak charger it cant over charge unless i for get to unplug it lol.thanks.
Logged

Bridkid

  • Full Mayhemer
  • *****
  • Offline Offline
  • Posts: 191
  • Location: Sunny Bridlington
    • Bridlington Model Boat Society
Re: charging nimh packs
« Reply #5 on: January 20, 2007, 08:28:20 pm »

Best of luck with the weather! Our lake here in Bridlington is more suited to a model surfer at the moment!
Cheers,
Ian
 >:(
Logged

justboatonic

  • Full Mayhemer
  • *****
  • Offline Offline
  • Posts: 1,516
  • Location: Thornton Cleveleys
Re: charging nimh packs
« Reply #6 on: January 20, 2007, 09:30:17 pm »

Nimh cells should not be slow charged to balance them, this method only applies to Nicads. The cells should be 'balanced' on a proper discharger which should bring the all the cells in a pack down to a common voltage (typically about 1 volt).

NimH cells should not be trickle charged. For best results, charge at about 4 to 5 amps max, do not let the cells get hot to the touch and use a charger rated for NimH cells. As has already been pointed out, they have a different charge characteristic to NiCads. NiMh cells can be 'peaked' again prior to use but NOT if alread very warm.
Logged

martno1fan

  • Full Mayhemer
  • *****
  • Offline Offline
  • Posts: 2,472
  • Location: Blackpool
Re: charging nimh packs
« Reply #7 on: January 21, 2007, 12:48:11 am »

well the place i bought the battery told me id be fine using this charger for the nimhs ? and i did use it and it charged them so ill be trying them today.seesm everyone has different ideas on this which is very confusing lol.
Logged

Bridkid

  • Full Mayhemer
  • *****
  • Offline Offline
  • Posts: 191
  • Location: Sunny Bridlington
    • Bridlington Model Boat Society
Re: charging nimh packs
« Reply #8 on: January 21, 2007, 09:58:44 am »

Which charger did you buy? I use a Ripmax Pro-Peak and each time I fast charge I set it to discharge first which takes all the cells down to low voltage, waits 3 minutes and then fast charges to peak. I still slow charge every so often and I haven't ruined a pack yet. I always keep my cells fully charged too, but then the next time I use them I discharge and re-charge before use.
Cheers,
Ian.
 8)
Logged

FullLeatherJacket

  • Guest
Re: charging nimh packs
« Reply #9 on: January 21, 2007, 12:10:53 pm »

For what it's worth I found this link:
http://www.powerstream.com/NiMH.htm
Makes sense to me. Make up your own mind.
Logged

Bridkid

  • Full Mayhemer
  • *****
  • Offline Offline
  • Posts: 191
  • Location: Sunny Bridlington
    • Bridlington Model Boat Society
Re: charging nimh packs
« Reply #10 on: January 22, 2007, 06:52:41 pm »

All very technical stuff but I can almost understand it. Thanks for the link and info.
When it came to the time for me to change from Nicads to Nimhs all I did was ask a well respected racer who as already using them what to do in the simplest terms, so I guess my advice was 'mouth to mouth' so to speak. Ah well, each to his own as they say. As one of our club members says....... 'Ask 5 model boaters the same question and you will get 5 different answers', that's why he always prefaces his answers with 'I'll tell you what works for me'. Maybe I should have written that too.
Cheers,
Ian
 8)
Logged

martno1fan

  • Full Mayhemer
  • *****
  • Offline Offline
  • Posts: 2,472
  • Location: Blackpool
Re: charging nimh packs
« Reply #11 on: January 22, 2007, 10:57:13 pm »

LOL  ;D
Logged

martno1fan

  • Full Mayhemer
  • *****
  • Offline Offline
  • Posts: 2,472
  • Location: Blackpool
Re: charging nimh packs
« Reply #12 on: February 06, 2007, 09:31:49 am »

Well guys i chaarged the battery on the nicad charger iots only a cheap slow charger 250 ma and it worked fine.We tested the boat two weeks later as the weather hadnt been great till now and after an hrs boost up we took her out.WOW this battery seems to push her twice as fast im not joking she was doing 18 to 20 mph at a guess i couldnt beleive it.We did have one problem yours trully hit a buoy and she took off up and over it landing upside down oops.problem is at the lake we took her to theres 3 sides to it and th 4th has a boom across deviding it from the main lake.Where did it end up? yep you guessed i had to wade in to get her,knee deep in mud and waist deep in water yuk in fact if i hadnt had the boom to hold onto id still be there now lol.Lucky for me the boat wasnt damaged or wet inside which amazed me as the hatch isnt water tight  ;D.So yes you can use a slow nicad charger to charge nimmhs as the manufactures of these batterys had told me .
Logged
Pages: [1]   Go Up
 

Page created in 0.086 seconds with 21 queries.