Chargers for Cycling NiMH Batteries

[David Hayward]

Does anyone know of a battery charger which can cycle NiMH rechargeable batteries up to 5 times while still allowing each cycle’s discharge and charge mAh readings to be viewed once the cycling session has finished?

 

I ask for the following reasons.  I have been using an IMAX B6 (50W) charger for some years. It is actually a clone-type from China, not an original SkyRC type and is reported to have been manufactured with somewhat inferior quality components compared to the original; hence its lower price. It worked well for several years but then the cycling started to give spurious results although for just charging it is still fine.  This is a Version 1 (V1) charger which, like the original IMAX B6 design, retained all the discharge and charge mAh readings for each cycle which could be readily viewed and noted once the cycling session had been completed.

 

However, I have found that the latest IMAX B6 V2 chargers which are rated at 60W, while having some additional features, only now allow the final set of discharge and charge mAh readings to be viewed at the end of any multi-cycle operation.  This does not give me any confidence that the cycling process has worked as it should, i.e. with gradually increasing discharge and charge readings with each successive cycle operation. I find this very unsatisfactory!

 

I have had correspondence with SkyRC about this issue regarding their D100 (100W) charger and also Overlander who market a seemingly identical charger but with their own name on it. The software seems similar to that of the IMAX B6 and they have also moved from V1 to V2 designs which I am told now have the same limitation as the IMAX B6 V2, i.e. only the final discharge and charge mAh readings are now viewable following any multi-cycle cycling sessions.  More disappointment!

 

Any advice on what battery chargers, if any, are currently available to meet my specific requirement would be much appreciated. I fly a range of range of ic model planes and currently only use NiMH rechargeable batteries for Tx and Rx purposes although would ideally like to have the flexibility to handle LiPos in the future should I eventually move into electric flight. 

[John Lee]

I very much doubt a present day charger that can do this.

 

In the days when NIcd's and NiMh were much more popular there were a number of chargers that offered cycling and recording capabilities, I've still got my old SM Services Charger/Cycler/Checker stack. Specifically the Robbe Infinity Peak Power 8153 has what you are looking for. It could be programmed for up to 99 cycles and recorded the capacity data for the last 5 cycles. Problem is it was produced in the mid-90's and is long our of production, but they still come up on eBay occasionally. 

 

https://www.rcgroups.com/articles/ezonemag/1996/infinity.htm 

[David Hayward]

Many thanks John for your reply - much appreciated. I rather suspected that any replies I received would be along the lines you have indicated. It seems that I shall probably just have to accept that technology fashions don't stay the same for ever.  I too have old SM Services equipment - a Battery Master & a Battery Master 2 but, as you will know, each charge/discharge cycle has to be set up afresh each time and the max. charge rate is limited to 400 mA.

[PatMc]

@David Hayward I think one of these chargers would meet your needs. You could download the instructions from the post & check. I have one from way back, it's a very good charger & my first choice for any non lithium battery charging. 

[Ayrton S]

Anybody know where I can find a circuit diagram for an S.M. Services Battery Master? I found a Data Sheet on the Wayback Machine listed elsewhere

[Phil Green]

One cycle should be enough to measure a NiMh as the capacity doesnt vary with 'memory effect' like a NiCd, I do occasional capacity checks too but each pack only needs to be done once so its not much trouble to do it manually 😀