Charging SAFT NICAD battery packs connect ser/par

Get 2 cheap battery chargers at Wal-Mart. Hook in series to charge 25V. 2 diodes in series will reduce your voltage output to 23.8V. Make sure the diodes are heavy duty enough to handle the wattage. "C" cells? Why not use 2 motorcycle batteries or car batteries? Nicads are not a good choice either. You may end up stranded because of memory effect. Regards, Keywalker

Thanks for info. The nicads would get a full discharge and recharge on my two days off, to counter the memory effect. On the 2f1r ev car that I plan to build, most battery weight has to be concentrated on the front wheels for stability. The nicad assymbly's can be constructed in flat packs and put in tight places to keep front end of car low. For batteries I would need eight 220amp hour six volt golf cart type, tied series parallel for the current and voltage I would need. The price is $100 a pop (not bad, I even have a charger to charge them) I already have the nicad packs that I used to construte some solar powered patio lights. They have been going strong for over two years. Once a month I change them out and cycle them.

I guess I misunderstood what the nicads were for. I still don't understand what they are for. If you are using golf cart batteries, why do you need "c" cells? Also, even changing them out and cycling them will not prevent them from loosing the ability to hold a charge over time. They are usually only good for 3 to 5 years under ideal conditions.

What I want is to be able to build a charger that can charge these nicads in groups of 5 (5 @ 4C (5volt) cell packs wired in series with a total of 50 packs tied parallel. Charged by 110 volts AC 60hz with a variable of 15 volts{for charging by unregulated generater or solar panel}). With the ability to automatically charge (with a discharge circuit to fully discharge all packs to avoid memory build up) and monitor each pack individually at charge and discharge rates, as well as temperture of each pack, with a circuit that can control heating and cooling of said packs (must be setable). Plus must have a control panel that I can monitor charge, tempature and also discharge rate of each pack, also alarm circuit that warns me of improper charge, discharge, heating, cooling (must be setable) of said pack via pack #. Must be compact and as light as possible.

SAFT nicad 4 (C battery size)
by your test 32 x 30/360 [Hr] = 4v x 5pks in series = 20V 2.7AH
* Any equipmet/Assy rated for 24V has +- 3V ratings .. nothing to worry !!!
your battery-packis 20V/2.7AH
As per your Calc it can deliver 32A for 30 sec
What is the power consumption of your drive at what speed[of drive not the motor]
By working back you can get the survival for time.

I can't understand how U will have the Charger onboard ??????????

Batteries are never forced-cooled, but never used at accellerated/lo temps than rated. Their life expectancy & capacity [ie AH] decrease.

They are 1.25 volt per cell and there are 4 cells per stick by my understanding that is 5 volts per stick and 5 stick per pack in series is 25 volts x 50 packs tied parallel is 133AH. (I'm guessing since I am not an engineer that is why I want help) since my top speed is maxed by law at 40 m.p.h. and I only have to go 3.3 miles one way to work in a 879 lb vehicle (including me). While at work for 9 hrs vehicle will be charging. Then when I return home vehicle will be charging for 14 hours. As of the motor is 24V at 70 amps hooked to a curtis controller and will be hooked up to a standard transmission. In my days of fast charging nicads for radio controlled airplanes the cooler you kept the battery pack the longer they lasted (I was just thinking that if you kept battery packs at their best temp for charge and dischage temps they will last longer also taking into account of ambient air temps year round. All and any help greatly thankfull

My dear:
"25 volts x 50 packs tied parallel is 133AH."

Batteries [& Generators]* are never connected in parallel as on load to share, low battery will be draining the good battery(s) instead of sharing the load.
You have to use 133AH [or some what smaller if could serve the purpose] batteries.

* unless you have very sophisticated power-sharing Controls.

You are surelly complicating your life a bit more that I would suggest to my enemies. Forget NiCads, memory will get to you sooner or latter, Get a good 24 V Charger and forget the water. And , do you intend to use regenerative braking? In any case, Lead Acid, car or motorcycle size will have a much longer life. If you have the $$$$$ go for Lithium Ion, but that is another story

Are you handsome? You better be because ugly guys never get picked up hitchhiking and you will be doing a lot of that "down the road".

NiCads will fail you for all the reasons listed. You should do some more research on the various technologies to better see what is out there and how well it works. Prior art can save you a lot of heart burn your thumb from pointing out.

Have you considered an anti-disintegration machine? They have two spoke wheels and two cyclic offset pedals with a multi-speed chain driven sprockets. They do not require batteries and very healthy form of transport (unless you get hit by a motorized vehicle). There is also a recumbent version if you prefer that seating position. And if the kid in you ever comes out you can always get some cloths pins and playing cards to dance in the spokes. Ah, brings back old memories of sunny warm summer days with the old Schwinn, some lemonade, and barefoot fishing down at the old creek without a hook and worm.