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Discussion Starter #1
I'm thinking about converting my Honda Goldwing into a BEV, with an AC23 motor/controller and 120vdc Toyota Prius NiMH battery pack. Batteries are estimated at 180 lbs, motor 60 lbs, about 70HP and 128 ft/lbs of Torque. Has anybody tried anything like this? Am I on the right track?
 

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Yes, lots more on elmoto.net

My first bike used an AC20 and headway cells. I wouldn't use NiMH. I'd use lithium if I were you. There's plenty of lithium out there, like Leaf, Volt and Bolt cells.
 

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Discussion Starter #3
I'm thinking about converting my Honda Goldwing into a BEV, with an AC23 motor/controller and 120vdc Toyota Prius NiMH battery pack. Batteries are estimated at 180 lbs, motor 60 lbs, about 70HP and 128 ft/lbs of Torque. Has anybody tried anything like this? Am I on the right track?
Appreciate the advice frodus, but I already have the PRIUS batteries so they are a no cost bonus. I have worked out a unique BMS/Charger solution that is working good for me, and they have good energy density/weight ratio. How did the AC20 work out for you? Enough power? What voltage did you run it at?
 

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Ran 96V, had good power. The batteries are pretty heavy, but if you have em and they work, great. Might need to tweak the controller battery cutoffs a little, but it's a good package. This was back in 2013 or so, so quite a few changes since they made the AC20. The AC23 is a newer design and better materials in the rotor and stator. The controllers are also, likely better. If it's 120V nominal, you may need to jump to the 1238 that does 144V. The 1238-7601 does up to 130VDC max.
 

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Discussion Starter #5 (Edited)
Thank you, that is what I was hoping to hear. Sounds like I am on the right track.

Here is more information on the battery packs I am making. They were initially designed for Golf Carts. A Golf Cart (36V) typically uses 6 Deep Cycle 6VDC Lead Acid batteries at 60-70lbs each or almost 400 lbs in total weight! A change out of these batteries happens about every 300 charges or so and costs roughly $800.
Those numbers floored me, it seemed really inefficient. So I looked at LiFePO4 batteries, trying to come up with something better-- but their cost was way over $800 especially after the Battery Management and Charger is figure in.

My niece had a Prius that died so I had access to the batteries. They looked promising. A pack of 6 was only 27 lbs. So I made my own bars to connect the batteries from 0.060 x 0.50" aluminum bar stock that I picked up at a Farm Store. And used 5mm brass nuts to secure them.
My first attempt using 2 packs to replace the Lead Acid batteries failed. The batteries bloated up like a toad bluffing a predator, and quit putting out juice. I learned 2 things; first you can't put too much of a load on them for and extended time and second they are much safer than LiFePO4 batteries-- they don't get hot. Because of their crystalline structure they react to overcharging/overloading by swelling and shutting down. And the charger for Lead Acid batteries wouldn't work for the NiMH ones.

My second attempt using 3 battery packs worked like a charm. Better power at 51 VDC, much less weight at 81 lbs, extended range at 1000+ charges and they were cheaper to boot. After a lot of searching and testing I found the following system works very well and can be scaled up for any Voltage/Amperage you might need;

PriusCells.JPG
This is a single cell rated at 7.2VDC nominal and about 1/3 kWh.
Bars.JPG
The Bars are 0.060"x0.50" aluminum bar stock with 2-7/32"(6mm) holes 21mm apart.
36VDC-Pack.JPG
This is the 36 VDC pack using 6 batteries, which weighs 27 lbs.
Charger.JPG
This is the charger that works great with these NiMH batteries. It is a Tenergy - Universal Smart Charger, Model: 01005, for 7.2-12V NiMH/NiCD batteries.
CorrectHookup.JPG
I use each Charger to charge two (2) cells, note the included Thyresistor placed between the batteries to sense heat.
FinishedPack.JPG
The finshed 36V pack should look like this. Newer NiMH batteries don't develop as much "memory" as the older ones. They can take a total discharge (I've gone as low as 0.3VDC each cell, and they recover completely with any "memory" erased.)

This setup is naturally self balancing and I see no need for expensive Battery Management Systems. Each pack will run all day on a 65-70 Amp draw, with surges of up to 240 Amps. So I use the appropriate number of packs for the motor's steady state and surge current requirements.
 

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Newer NiMH batteries don't develop as much "memory" as the older ones.
NiMH have never have memory. Nor have NiCads.

It was an 80s myth that has stuck around for 40 years.

"Memory" existed once, for one satellite that spent exactly half it's day in the dark, half it's day in the light, and got charged down to the exact same point every day. Eventually it needed a full cycle to restore it's capacity. That's it. That's the only memory effect that ever existed.

This setup is naturally self balancing
Any series chain is self-balancing, by virtue of being in series. It's when small differences in the pack start to add up that they become unbalanced.

NiMH can be overdischarged with the only consequence being heat (the wasted energy), so that's the mechanism that balances them.

Far as I know, no NiMH system ever had a BMS.

they have good energy density/weight ratio. [...] This is a single cell rated at 7.2VDC nominal and about 1/3 kWh. [...] 36 VDC pack using 6 batteries, which weighs 27 lbs.
Prius batteries, far as I can tell, are in fact 7.2v, but only 6.5ah = 46.8 watt-hours, and weigh about 1kg.

Yours weigh 2kg.

So maybe yours are double-sized? Still not 333 watt-hours.

But regardless, you're looking at under 50wh/kg... 20% of what lithium would get you.

It's passable for a car, but, on a motorbike with weight and bulk limitations, I think you're likely to be disappointed by the range.

Maybe I'm wrong, but, might be worth doublechecking your battery specs.

...

BTW... I'm looking for a salvaged Prius for the controller (and maybe the motor), do you still have it, or are you looking to scrap parts off of it?
 

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Discussion Starter #7
No we don't have the Prius any more. Thank you for your input. I see a lot of conflicting numbers on the amount of energy in these batteries. I've seen the 6.5 Ah rating and yet the Prius 28 cell battery is rated at 8.8 kWh, that doesn't jive? In actual testing I've seen a huge range in the amount of energy in these batteries based on how your do the last 10% of their capacity.
Factory new ratings for the battery are a maximum voltage of 9.1 VDC, while used one are sold that can only support 75-80% of that range. If you use cells that will support a full 90% charge at 8.3 VDC the range I've seen is actually pretty good.
I haven't seen any Lithium batteries that come near the $25 each price these are available for. Do you have any suggestions that are better value per watt in the LiFePO4 batteries, when you factor in BMS and charger???
 

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I noticed a few of you here have used, or know the Sevcon Gen 4 controllers. I really need some help to enter in the final codes. And clear some faults.
Can anyone help,advise or point me in the right direction. Help from Sevcon is not forthcoming.

I am using a PM three phase motor (four Pole) mounted and geared to run at 6000 RPM, 60 MPH top speed.
Batteries will be 18650's at about 4.8kw in a full motorcross bike frame/suspension.

I have all this setup on the bench right now, using, nominal 72v LAB for testing.
Tyco Contactor /Gen 4 size 6/ Ixxat connected to our laptop/ and the wiring harness made for the Sevcon. Also a Domino throttle and a forward switch.
Every thing else is Not Mapped, except for the contactor's. I seem to always get the same fault. 0x5000.

Been through the Manual a couple times but don't want to enter something that
cant be undone. There is no go back button, unless I save the the dcf file after every change.

Progress.
I can get the motor spin for a brief second and then get faults and have to reset. Not long enough to commission the sin cosine sensor, which I was told needed to be done.
Seems like this may be one issue along with others.

Questions.
Can the line contactor be set to 12 volts. This is what the Tyco coil is rated at. Running in from one of the 12 volt batteries now. I belive this can be controlled thru the controller?
Is the throttle voltage supposed to be 0-12 volts Up in voltage as speed increases or down in voltage. Right now it is set going down which seems counter intuitive.
Does the voltage have to be a specific setting? Like 0-5v.

Thanks in advance.
Mark
 
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