Toyota Prius Battery packs

[mustangman]

 I have some helpful information regarding the Toyota Prius (or lexus) battery packs. The individual cells are 7.2 nominal volts and 6.5Ah rated. The entire packs (2001 Model) has a rated capacity of 274 nominal voltage with 40 indvidual cells. The pack is NiMh and manufactured by Panasonic's EV battery division in Japan.
  The best thing is that the entire pack can be purchased for next to nothing at a local auto salvage yard. Please explain to them that you do not need an entire "perfect" pack but a few cells to make a pack for an E-bike conversion. I personally got lucky and was offered an entire pack from a 2001 model for free!!! 

[OneEye]

That's awesome!  5 cells for a 36V 6.5Ah pack, or 10 cells for 36V 13Ah!  The price is about right too  .

How many cells are you going to use?  How are you going to wire them? and what charging method/BMS are you going to hook up?  (and what are you going to do with the other cells that don't go into your bike ?)

[mustangman]

 I was thinking of making 13 to 27Ah pack @ 48V if the weight wasn't too prohibitive. (wire them into 36 or 48 voltpacks and then wire them in parallel to make 6.5 to 27Ah system) That way I could make a 10-15+ mile round trip with no pedaling @ 25+ Mph.  I am sure their are more "totaled" hybrids out there with a "damaged" battery pack ready to harvested for a E-bike conversion. The smart charger for this homemade pack could be picked up for around $70 or less. 

[myelectricbike]

All but one salvage yard in our area still sell parts from wrecked or junked cars considering the amount of space required to store the remains. How many cycles do you figure are left in the cells you picked up?

[mustangman]

He assured me that they had at least 2 years left depending on usage. The reason for bargain price was that a couple of cells had corrosion on the connections, this makes then not suitable for reuse in Prius/lexus cars. The worst case scenario is that I can not use them and I can turn in the pack to a local Toyota Dealer for recycling.(Toyota corp, pays up to a $200 bounty to the dealer on expired packs to keep them out of the landfills, sorry they won't share the booty!) The key to this "experiement" is that you tell Yard salesperson you do not need something "NEW" and perfect but "Used" but still in usable condition. The yards are there to make money, however you can negotiate a price for the item you want. Out of 40 possibel cells, you only need 5 to 10 to make a pack for an E-Bike or 1 out of 4 for 14 Ah pack or 1 out of 8 for a 6.5Ah pack needs to be acceptable. These odds are far better than you would get at any casino or lottery!!!

[myelectricbike]

Hummm... I wonder if Panasonic might start supplying battery packs for ebikes?

BTW - here are some links you may find of interest...

Thermal Evaluation of Toyota Prius Battery Pack
Toyota Prius
Toyota Prius II Battery Pack
Technology Snapshot - Prius
Prius History
Toyota Prius Hybrid Owners Hacking To Increase Gas Mileage
...for the complete listing

[mustangman]

 Thank You for the additional information. As more and more hybrids bite the dust (totaled in an accident) , the chances of finding a suitable battery pack increases. Oh, don't forget about other brands and models of cars to scavange from like ford escapes and honda civics.

[myelectricbike]

Truth is I've had to put my bike in the garage and start peddling until I loose some weight so until I do lighter batteries are going to have to wait.