[Mike99]

Hello everyone,

I am working on a project to design and build a small hybrid vehicle.
The design will be to run two PERM PMG 132 electric motors
with the followings specifications:
1) 72 volts
2) Maximum current of 400A (continuous current of 220A) - 200A peak
current per motor (110A continuous current per motor).
3) Be able to run at maximum power (72V and 400A) for at least 10 seconds.
4) Weight is of concern (preferably under 50lbs)
5) Cost is of concern as well (Preferably under $2000)

I have been searching for a battery system that can satisfy these needs but it is difficult to find batteries that can discharge at this rate.

Could anyone recommend a battery system (or combination) that would be able to satisfy the above requirements?

I have been looking into NiMH and have been leaning towards this chemistry as it seems to be the simplest and cheapest.
Has anyone had any success using small NiMH cells in series (such as hobby D cells) to power high power motors? Or does anyone know of other suppliers that have high discharge NiMH batteries?

Or could Lithium based batteries be the only solution here. (I'd prefer to stay away from these due to the cost and need for a BMS system - which would be required).

Thanks in advance for any replies,

Mike

 

[DIYguy]

Hello everyone,

I am working on a project to design and build a small hybrid vehicle.
The design will be to run two PERM PMG 132 electric motors
with the followings specifications:
1) 72 volts
2) Maximum current of 400A (continuous current of 220A) - 200A peak
current per motor (110A continuous current per motor).
3) Be able to run at maximum power (72V and 400A) for at least 10 seconds.
4) Weight is of concern (preferably under 50lbs)
5) Cost is of concern as well (Preferably under $2000)

I have been searching for a battery system that can satisfy these needs but it is difficult to find batteries that can discharge at this rate.

Could anyone recommend a battery system (or combination) that would be able to satisfy the above requirements?

I have been looking into NiMH and have been leaning towards this chemistry as it seems to be the simplest and cheapest.
Has anyone had any success using small NiMH cells in series (such as hobby D cells) to power high power motors? Or does anyone know of other suppliers that have high discharge NiMH batteries?

Or could Lithium based batteries be the only solution here. (I'd prefer to stay away from these due to the cost and need for a BMS system - which would be required).

Thanks in advance for any replies,

Mike

Headways. if u used the 8Ah cells, 25S3P or even 4P would still be under $2000.

 

[Mike99]

Thanks DIYguy,

Those batteries look great.

They list the 3min maximum discharge as 160A. Would it be possible to get 200A for 10s?

Im not exactly how batteries work in this regard.

Does anyone know if I could get 50 cell BMSs for a reasonable cost?
Temperature and voltage monitoring.

 

[DIYguy]

Thanks DIYguy,

Those batteries look great.

They list the 3min maximum discharge as 160A. Would it be possible to get 200A for 10s?

Im not exactly how batteries work in this regard.

Does anyone know if I could get 50 cell BMSs for a reasonable cost?
Temperature and voltage monitoring.

Every time you parallel another one, u add 160 amps of discharge current... therefor the 25S3P would give you 80 volts at 480amps. 4P would give you 640 amps. Of course you would have voltage sag at higher currents.

First of all, you don't need anything for paralleled cells. So, if you were to use a BMS, it would only be for the 25 series ones. There are some options here... do some BMS reading.

Instrumentation is available. Checkout the highvoltage version of the Cycle Analyst.

edit.... read this thread...http://www.diyelectriccar.com/forums/showthread.php/bms-not-bms-53768.html

 

[Salty9]

I don't know it for a fact but I've read that Toyota uses or used NiMH batteries in the Prius. Whoops, Just found this on the web:

http://www.greencarreports.com/blog/1041538_why-the-2010-toyota-prius-doesnt-have-a-lithium-ion-battery