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Discussion Starter #1
Building a Sir. Anthony Colin Bruce Chapman 7 (Lotus)
Haven't figured much out yet, and hoping for a great thread here, please point me to some useful information.
Have most auto parts, like rear end, springs, brakes, hubs etc, and all the metal required. As well as a beauty Caterham (10" longer) mold. And the skills to fab it all.
Aside from that, I will be available. Lurking.
Warm Regards from frozen Canada
James
 

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Having chosen the design, you have sort of painted yourself into a corner; I don't know why people do that in a completely custom-built car, which could be designed to work with the electric drive components. For instance, if you are using a live beam axle (not independent rear suspension), you can't put the motor in the back where the designer of an EV would put it if possible. How much flexibility is there in your design?

Battery space is certainly a problem, especially with the traditional "Seven-esque" powertrain layout. Duncan addressed that by putting the motor where the transmission would normally be, leaving the whole engine compartment for battery. That means, in his case, that the motor drives the wheels with only the final drive unit for gear reduction, so there motor can't run at very high speed (which means it must be large) and the gear ratio can't be changed as you drive (as with shifting a transmission) so the motor is usually far off its ideal speed for power and efficiency... the fix, again, is a big motor.
 

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Discussion Starter #4
Thanks
I have not done the measurements yet

Dorman - OE Solutions 587-007 Hybrid Drive Battery

Seem to fit, just roughly measuring. I haven't really addressed the numbers. Still hypothetical. I hope to be able to make room where needed. It is close
 

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I have not done the measurements yet

Dorman - OE Solutions 587-007 Hybrid Drive Battery

Seem to fit, just roughly measuring. I haven't really addressed the numbers. Still hypothetical. I hope to be able to make room where needed. It is close
Physically, it might fit in the engine area. Do you realize how little energy capacity this battery has? It's from a Toyota hybrid, such as a Prius, so it is a NiMH (not lithium ion) battery with about one kilowatt-hour or less of capacity. The Dorman listing says that it fits a Prius Prime, but that uses a very different battery from all of the other models listed. Even a Prius Prime (plug-in hybrid) battery would need to be from the second generation of Prius Prime to have enough capacity to be close to useful.
 

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I was sure it was being sold as a 2012 plug in? oops
Even a 2012 Prius Prime battery would have a capacity of only 4.4 kWh, good for a range of something like 12 miles in the Prius (and likely not any more in the Seven). That's less than half the capacity that a typical DIY EV conversion was getting when CALB LiFePO4 cells were popular, and less than one-third of the capacity of more typical plug-in hybrids such as the Volt.

The newer generation of Prius Prime has a battery with twice that capacity, which even looks like it could be re-configured (opened up and modules re-arranged in a new box) to fit in the front of a Seven... but that's still not a lot of capacity.
 

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Discussion Starter #8
ah, ok
thank you

what would you do, what do you figure the best source is. price availability etc please
 

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Building a Sir. Anthony Colin Bruce Chapman 7 (Lotus)
...
Have most auto parts, like rear end, springs, brakes, hubs etc, and all the metal required. As well as a beauty Caterham (10" longer) mold. And the skills to fab it all.
Since you're at least semi-committed to a specific body shape, do you have the dimensions of the engine space? This is supposed to be an introduction thread, not a build thread, so rather than trying to work out design details I'm really just thinking of factors to consider.
 

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what would you do, what do you figure the best source is. price availability etc please
I think combining multiple small packs from hybrids is probably more cost and effort than it's worth. A complete pack (or most of a pack) from a larger-capacity plug-in hybrid makes more sense; since the Chevrolet Volt is by far the most common plug-in hybrid and has a good battery it's the popular choice... you can even occasionally see one here in Alberta ( a Volt, that is - I don't know about the availability of batteries salvaged from them).

The obvious alternative - especially for anyone wanting a lower-voltage battery which could be assembled from part of a typical 360-volt EV pack - is to salvage from a common EV. That means choosing one of the models which are sort of common here (Nissan Leaf for simplicity and availability, Tesla Model S/X if you want a big battery, or whatever you can find), or importing from the U.S. (which seems like a shipping challenge to me).

I think that suitable sources and prices depend heavily on your location.
 
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