Rosemary Ainslie circuit demonstration on Saturday March 12th 2011

[Magluvin]

Hey Stefan

that is very interesting on the nimh batteries.  ;]

I have 3 electric bikes, 1 is a tidalforce m750 which uses 30 D nimh cells in the front wheel hub. 
They are ready for change. Do you think I can revive them this way? Or even better yet, get more than 20 mpc  miles per charge after treatment?

Sorry  to be off topic but this seems to be very important to anyone using these batteries, as they are $18 each, for the good ones. =]

Thanks for the info

Mags

[hartiberlin]

Hey Stefan

that is very interesting on the nimh batteries.  ;]

I have 3 electric bikes, 1 is a tidalforce m750 which uses 30 D nimh cells in the front wheel hub. 
They are ready for change. Do you think I can revive them this way? Or even better yet, get more than 20 mpc  miles per charge after treatment?

Sorry  to be off topic but this seems to be very important to anyone using these batteries, as they are $18 each, for the good ones. =]

Thanks for the info

Mags

Sure !

Just pulse them via a Joule Thief or use a transformer
coil with a relay for the make-break of the current.

The BackEMF pulses will revive them perfectly and also
put a great charge into them.

But only do this with Lead Acid and NiMH.

This will not work with Lithium batteries
as these are built different and
can NOT be charged like this.

But with NiMH batteries normal dc current chargers are a waste,
cause they always make the batteries after a while unusable.

Using BackEMF charging is a great way to always keep NiMH batteries
fresh and get them more capacity.

Regards, Stefan.

[hartiberlin]

P.S: Yes you will get more than 20 Miles per charge,
if you charge them up with good BackEMF pulses.

YOu only have to watch the batteries, that they don´t get too hot
during charging, otherwise they dry out and this is the only way you can destroy them
this way.

So use BackEMF pulse charging this way, that they don´t get too hot to
hold in your hand, mildly warm is okay, but not too hot.

So reduce your pulse frequency, if they do get too hot or use a smaller coil
which stores less energy or use a different on/off setting ( PWM ratio for the input current
into the coil).

Regards, Stefan.

[Magluvin]

Thank you Stefan. =]

I have to take the hub apart to do this as there is extensive circuitry in both wheels.  I cant even fully drain them either because of this, as nimh do have a memory thing like nicad, just not as bad.

Very good, will try and report as to the outcome. ;]

Mags happy

[hartiberlin]

Magluvin your are welcome.

Yes, take the NiMH batteries out and try to recharge them
with a bigger joule thief style BackEMF charger.
Instead of the LED you can connect your NiMH batteries.

The Voltage Spikes without the batteries should be at least 20 Volts Higher
than when the batteries are connected.
If you connect all NiMH in series to the output, that means, if you have for instance a 36 Volts
NiMH pack you should at least hit them with 60 to 100 Volts positive voltage spikes,
so this gets effective.

Please keep attention to the temperature of the battery pack
and only charge them this way, if you are near them and not let them
charge unattended.


Regards, Stefan.