Regenerative controller vs. lithium cells

[Towi]

Hi all,

I wonder if the new regen controller may be used with lithium batteries. Does somebody know, if there is a (perhaps programmable) overcharge protection during regeneration ? I'm especially interessed by using the DeWalt A123 cells.
Are specifications / user manuals of the controllers somewhere out there ? I wasn't able to find one.

Thanx
Thomas

[myelectricbike]

There do appear to be many circuit improvements over the standard controller, but accommodating battery type other than lead acid does not yet appear to be one of them.

[erdurbin]

By the guy I am in connection with at Foxx battery systems, he says a regen controller would work great with the LiFePO4 packs and encouraged I look into getting one for my kit. Since they are as safe as SLA, he said I should go for it. I would never worry about overcharging because you are not going to be putting back into the battery more than you take out of it by riding (unless you go downhill all the time and freewheel, then why would you need an ebike).

I will keep everyone posted on my LiFePO4 pack I will be receiving in a few weeks. I may opt for the regen controller if I like the pack enough.

[Towi]

Great, that sounds encouraging.
erdurbin I'm already very curious about your experience of using a LiFePO4 pack on it. Is it a modified DeWalt batterie ?
Unfortunately from my home I start downhill but I could start w/o engaging regeneration (or empty batteries).

If I understood well, the regen controller is supplied together with a special thumb throttle which has something like a forward range for acceleration a neutral 0 point and a backward range for progressive regeneration/braking. Is that right ?
May a normal (or adapted) twist throttle do the job as well ?

Thomas

[myelectricbike]

Some throttles are not interchangeable. For instance my 48 volt throttle with not work with any of my 36 volt kits and vice versa. I can no longer give out info on my regen because I can no longer get it to correctly sequence the phases after a sensor failed and was replaced.

[Towi]

Hope you get it work again soon !!

How do you engage regeneration. Is there a switch for changing between assistance and regeneration, or is there need of a special throttle with a neutral point in between ?

Thanks

[myelectricbike]

Don't know for sure all the intricate details of the regen microcode but my guess is that it simply senses when Counter EMF is greater than applied voltage such that when Counter EMF is greater at whatever speed it sends the excess current back to the batteries. Thus if you start pedaling at full throttle (about 3/4 speed of full throttle using a standard controller) producing more and more Counter EMF then when the Counter EMF finally catches up with applied power at some point beyond that you will enter sweat mode and begin charging the batteries. However, prior to the Counter EMF catching up your pedaling is still helping to conserve battery power by not using as much. Even though I have hills the majority of my recharge I think comes from slowing down and breaking. Sure hope I can get it working again.

[johnbear]

I just came across this topic. Does anyone have any more information on the above mentioned throttle? How do you buy it?

Thanks.