Using the EV calc, if I go for 144V, the 6V bats alone weigh like 1460lbs. With the max load at 992lbs with stock suspension, will I be losing enough weight without the engine, fuel tank, etc. About how much is that?
The Zapi H2 is not a too good to be true controller. Just hard to get and then you need to match it up to a good motor with interpoles. Also the H2 and H3 are not cheap. They are very expensive. I am getting a new quote on the H2's this week. You don't find used ones because they are still being used. They are good.
my bet is you will be FINE with 120v worth of 8v batteries. Floodies will get you further, but have voltage sag and require occasional watering. AGM are more expensive and have lower range, but peppier performance with less sag.
Series DC motors with interpoles are not perm magnet motors. I have one. I have an 11" Kostov Series DC with interpoles. The interpoles help reduce arcing and flashover when running at high rpm's and when running in regen mode. My Kostov is a SepEx motor in that the field/interpole field windings are controlled by a separate power source. So is my Military Starter/Generator but that one is also a modified Shut motor with fine wire field/interpole windings.
To regen I believe you need a separate power to the field only when in regen mode.
With a perm magnet you always have charged field windings so it will always do regen.
AC motors are all together a different beast but I think the same principle applies.
Use 8 volt batteries and you can do 144 volts no problem. 6 Volters would push your limits. The weight limits I posted include the engine. The VW engine does not weigh much so you don't get much back there but some. You could do 120 with 2 volt batteries. 18 6 volt batteries is about 1100 lbs. Just about at your limits. That is the problem with lead acid batteries. Weight limits. Arrrrrrg.
If you used a DC motor with interpoles and neutral timing and kept your transmission and used the gearing you could do regen and not kill your motor or efficiency. Using the transmission will keep the motor within factory specs and give you more torque at lower rpm's. The interpoles will allow you to run higher voltages. At lower rpm's and neutral timing you will have more pulling power on the road. Folks advance their motors to give them higher rpms and to help reduce arcing with a non-interpole motor. Advancing reduces the motors torque but gives you higher rpm's. There is a tradeoff. I'd prefer a neutral timed motor with interpoles and have more available torque to the wheels.
The reason most do not use DC for regen is that they killed non-interpole motors and did not have a good supply of the interpole motors so they compromised and found that you could advance a standard series dc motor and have good power and rpm's but no regen. The option of no regen was pushed hard and it became the defacto norm. It does not mean you can't have a good fast machine with good power and some regen to boot.
Yes you'd have to be careful about using regen mode in a full pack but remember that a full pack does not last long. The main issue for regen is can your controller handle the power. Not the batteries. Most regen is for mere seconds and not minutes. I think the batteries can handle some high power input but can your controller. Not all controllers can handle high power so regen is not an option.
With weak field PM motors you always do regen. But not always do you need to shunt it to the battery pack. It could be shunted to a resistor and used a plug braking.
PM motors are limited in power/torque only because of the limits of Perm Magnets. Find a better magnet and you will have more available power/torque and better regen.
Was looking at pairing a M&C motor (27kw 144V 62kg model) with some Kelly controller depending on how it works out for neljoshua.
I also had a question about battery chargers and whether there is a 144V model that has programmable charging curves to be used with any battery pack (AGM, FLA, LiFePo etc), so long as you have the proper BMS in place for the bats. That way I can start with my UPS AGM batteries to break things in, and then upgrade to FLA or LiFePo later without needing to buy a new charger.
Oh and drum brakes. If my car is near the GVW (3274lbs) will the original brakes (assuming they're all tuned up) still be able to bring me to a stop when I need to. How much can regenerative braking help here?
Ideally, I'd like to have enough juice to go about 60mph over 30 miles flat, and still do 50 on 4% grade, although only for about 6 miles. All that without killing the lifetime of my batteries so I guess a 50% DOD to get the most out of them.
Another reason for LiFePo4 You'll get 80% DoD and still 2000 cycles instead of like 500.
I would build a 144v system using LiFePo4
7k on 50-160AH bats
OR
5k on 50-100AH with 1700$ BMS
Then look up the thread on ForkLift Motors.
Find a good one since time isn't an issue.
Full ForkLift, get everything you need from it save everything.
Once your project is finished Sell everything and scrap it for some $$$
3k left for controller charger and "Extra's"
Then after a while you can switch to a AC motor setup after the Fork'N'Free blows up.
Find a good one since time isn't an issue.
Full ForkLift, get everything you need from it save everything.
Once your project is finished Sell everything and scrap it for some $$$
Be productive. CL isn't a great place, not saying it isn't bad, just not great. Let your fingers do the walking, see if there are repair shops.. scrap yards.. etc.
What do I need to look for to know if an old VW transmission will work? I found someone selling 2 '68s, not sure if they are from buses or type 1/3. They are already pulled so I won't be able to see if they actually operate correctly. I suppose that all I can do is look for bad signs like rust, cracks, broken bits where the CVs and motor shaft hook in. Check to see if there's oil in it. I will for sure ask about their history. Are there any simple tests to see if the internals are ok? At $50 apiece should I assume they will need rebuilding?
What do I need to look for to know if an old VW transmission will work? I found someone selling 2 '68s, not sure if they are from buses or type 1/3. They are already pulled so I won't be able to see if they actually operate correctly. I suppose that all I can do is look for bad signs like rust, cracks, broken bits where the CVs and motor shaft hook in. Check to see if there's oil in it. I will for sure ask about their history. Are there any simple tests to see if the internals are ok? At $50 apiece should I assume they will need rebuilding?
Don't assume they need rebuilt. VW transaxles are very robust. Most likely just need cleaned. Some could have bad syncro's but most are fine. What kind of VW were they pulled from? Just 68 does no good. More likely they are from a VW bug. Should be just fine. Check for things that say very hard life like leaking things and gobbs of dirt and crud. You can not test out of the car. At $50 a pop even if they are bad you would not loose much except time. Get them both or get the cleanest one. They are old no matter what and they will have years of grime. If they are clean that may be a sign that they have been rebuilt recently. That is possible too. Get new seals for the tranny.
Unfortunately, I have to put my plans on hold because my friend, whose garage I was going to use, may be moving soon in the next month. This was unexpected because he wasn't planning on having to go through a divorce...
Also means that the squareback will likely be sold off before I can wrangle a new place to keep it. I'd buy the car and put it in storage, but I don't really have the extra money.
Hopefully things will work out and I'll be posting again here with an update.
Thanks for all the help so far!
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