Model Boat Mayhem

Technical, Techniques, Hints, and Tips => Batteries & Chargers => Topic started by: TheLongBuild on June 09, 2023, 08:37:11 pm

Title: 3-300 NI-MH7.2 V 3300MAH
Post by: TheLongBuild on June 09, 2023, 08:37:11 pm

We have a number of these which we use for the have a go boats, they were purchased February 2022 suddenly 3 of the batteries will not show as charging, using a standard Fusion charger, I have 3 chargers and it is the same with all 3 of them. 
I have tested them on other batts I have, even some which have not been charged for a number of years and they are all recognised by the charger .


Any one come across this before ?.


The Battery's were all bought from a reputable supplier so have no issues there that they were cheep stock etc.


Any thoughts ?. 

Title: Re: 3-300 NI-MH7.2 V 3300MAH
Post by: Colin Bishop on June 09, 2023, 09:14:08 pm

Do you have an older less intelligent charger to try on them? I usually use the Vapex Easy Charge ones although I do have more sophisticated chargers.

Colin

Title: Re: 3-300 NI-MH7.2 V 3300MAH
Post by: TheLongBuild on June 09, 2023, 10:48:30 pm

Not sure that I have, just tried an Mtroniks charger and that also did not recognise them but still worked for an old batt that we know does not keep its charge as quite old and has had a hard life..

Title: Re: 3-300 NI-MH7.2 V 3300MAH
Post by: roycv on June 10, 2023, 04:52:03 am

Hi i have found that some batteries need waking up.  I use a lead/acid SLA charger for about 10 minutes and then re-connect to the intelligent charger.  This seems to work.
Regards
Roy

Title: Re: 3-300 NI-MH7.2 V 3300MAH
Post by: chas on June 10, 2023, 09:59:17 am

Probably the cell voltages have dropped below what's recognised by the charger, as already said, put a charge into each battery either from an old charger or a good battery of greater voltage than the problem ones. It only takes 20 or 30 seconds to wake the battery up.
  I always charge my nimh batteries before ave to prevent this.

Title: Re: 3-300 NI-MH7.2 V 3300MAH
Post by: cos918 on June 10, 2023, 07:43:06 pm

on most smart chargers you can go to a manual setting ie not auto charge. Use that and let the voltage in the cells increase. Then switch back to the normal settings
John

Title: Re: 3-300 NI-MH7.2 V 3300MAH
Post by: TheLongBuild on June 11, 2023, 03:36:56 pm

Quote from: chas on June 10, 2023, 09:59:17 am

Probably the cell voltages have dropped below what's recognised by the charger, as already said, put a charge into each battery either from an old charger or a good battery of greater voltage than the problem ones. It only takes 20 or 30 seconds to wake the battery up.
  I always charge my nimh batteries before ave to prevent this.

No, Nothing. <:(

Title: Re: 3-300 NI-MH7.2 V 3300MAH
Post by: chas on June 11, 2023, 10:07:34 pm

??????. What did you try?

Title: Re: 3-300 NI-MH7.2 V 3300MAH
Post by: Tug Fanatic on August 28, 2023, 06:20:19 pm

Sorry wrong topic!