NIMH battery charger

Discussion in 'The Projects Forum' started by MMH, Mar 3, 2013.

  1. MMH

    Thread Starter Member

    Feb 8, 2013
    143
    4
    Hello there!!

    I was thinking of making my Super trickle nimh charger!! Will charging A batt with C/50 for a whole month cause any overcharge? Will C/100 Cause overcharge?

    Thanks in advance for your help!!
     
  2. wayneh

    Expert

    Sep 9, 2010
    12,087
    3,026
    I suggest visiting the battery university, and getting the datasheets from the manufacturer for the batteries you are using.
     
  3. praondevou

    AAC Fanatic!

    Jul 9, 2011
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    Overcharging with 1/50 C? I doubt it. I charge my cellphone battery with 1/2 C, doesn't even get warm.

    Make sure you don't exceed the maximum charging voltage.

    From Wiki: "The significant disadvantage of NiMH batteries is the high rate of self-discharge; NiMH batteries lose up to 20% of their charge on the first day and up to 4% per day of storage after that"
     
    absf likes this.
  4. MMH

    Thread Starter Member

    Feb 8, 2013
    143
    4
    I guess you are talking about LI-ion, not NiMH. Accordingg to what i have read, NIMHs are very prone to overcharging, if the charge is not terminated after full charge, unlike liion, Which- the longer you charge, the better.
     
  5. bountyhunter

    Well-Known Member

    Sep 7, 2009
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    Li-Ion are NOT allowed to be continuously overcharged. They use a very accurate CV charger to prevent overcharging.
     
  6. MMH

    Thread Starter Member

    Feb 8, 2013
    143
    4
    Sorry for that!!

    And now I dont think NIMHs will be oversharged at C/50. Will they??
     
  7. thatoneguy

    AAC Fanatic!

    Feb 19, 2009
    6,357
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    No, C/50 won't overcharge.

    C/20 is considered a "trickle charge".

    Some batteries, like NiCd, actually respond strangely to a lower charging current. NiMH can go a long time with C/50, though you may not be keeping up with self-discharge depending on battery condition and temperature.
     
  8. MMH

    Thread Starter Member

    Feb 8, 2013
    143
    4
    Thank you very much!!

    It seems quite awkward for me to ONLY ask help, doesnt it? So I was thinking of helping others and share my knowledge.My question is, How will I understand what new threads are being started and what posts are being given by other people in need?? can you please help me??
     
  9. bountyhunter

    Well-Known Member

    Sep 7, 2009
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    I think C/50 continuous is OK for most NI-MH, maybe as much as C/40 is OK.
     
  10. praondevou

    AAC Fanatic!

    Jul 9, 2011
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