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Discussion Starter · #1 ·
I'd like to convert a small car like a Geo metro or Geo tracker to run on lead acid. Im interested in using an AC motor. How many batteries would I expect to purchase to achieve the desired range if it even possible? I'm considering lead over lithium because of the cost. Sorry I'm not very knowledgeable. If someone can direct me to resources on estimating range, cost, acceleration, longevity, etc on different EV conversion configurations, I will be very greateful. Thank you.
 

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Don't do it...

300w/mi * 60 = 18kWh. For example at 36v (common forklift voltage) that is 500Ah. Here is an example battery Electric Forklift Battery 18-85-13-a, 36 Volt, 510 Ah (at 6 hr.) | eBay, it is 1300lb. Also lifespan of a deep cycle battery is severely shortened when it's cycled more than half way.

Also note the price - about $4000. For about $3000 you may be able to find a complete ~24kWh battery from a wrecked EV.
 

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Putting 60 mile range worth of lead on a Geo Metro is going to get you 60 miles downhill, once, and not have the power to take it back uphill.

There is no amount of shortcutting that makes lead viable (unless, maybe, maaaaaybe if you have and endless free supply of them).

A Geo metro is so small and so light, you can probably get 200 watt-hours per mile at highway speeds. So, you might get away with a 12,000 watt-hour pack. Pretty tiny.

Let's start at the beginning, so that you have a realistic approach to your cheapness and so that we're not being overly prescriptive of your questions.

What's your budget? What do you imagine this costing?

...

In other news, with current gas prices, I expect to see a flood of DIY Dreamers thinking "I'll make an electric car, and SAVE money!!" To which we can all tell them, no, go buy a used Leaf or add some batteries to a Prius.
 

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In other news, with current gas prices, I expect to see a flood of DIY Dreamers thinking "I'll make an electric car, and SAVE money!!" To which we can all tell them, no, go buy a used Leaf or add some batteries to a Prius.
Yeap, incoming. The cheapest/best thing anyone can do is get better paying employment. The extra 50 or even 100 bucks a week for gas is nothing compared to the amount of extra income over a year. I like high gas prices, gets the poor people off the road so I can get to work faster (_s)
 

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So, you want to tear a Metro to shreds?

For your conversion, it doesn't matter DC or AC. The car has low mass so will take off like a scared cat with a DC motor and a 144V battery.

96-144VDC is not generally deadly like the 400V AC stuff is...anyone doing a 400V conversion who's never worked with electricity or on cars, who is not working with someone who has, has a good chance of getting electrocuted. Electrocuted 💀
 

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Discussion Starter · #8 ·
What's your budget? What do you imagine this costing?
I
I'd like to spend about 15 grand max. I would buy a leaf, I looked into one, but the diminished range was off-putting. More concerning, the cost of replacing the batteries made me pass on it. If I have to reach lithium battery packs every 8-10 years for 6 grand I'm considering lead-acid (even if it's a <five year life span) if it's ultimately cheaper. If I convert the vehicle, I'll know how to service it.

Another reason I'm asking about lead acid is supply chains. Because most the world's nickel supply comes from Russia, the cost of NiCad and Ni Hydride and nickel containing lithium packs will go up. I'm considering lead because it may be cheaper and easier to acquire in the near future.
 

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Discussion Starter · #9 ·
Yeap, incoming. The cheapest/best thing anyone can do is get better paying employment. The extra 50 or even 100 bucks a week for gas is nothing compared to the amount of extra income over a year. I like high gas prices, gets the poor people off the road so I can get to work faster (_s)
I was trying to be polite and humble in my inquiry. I stated my lack of knowledge upfront. I really don't appreciate being insulted.
 

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I
I'd like to spend about 15 grand max. I would buy a leaf, I looked into one, but the diminished range was off-putting. More concerning, the cost of replacing the batteries made me pass on it. If I have to reach lithium battery packs every 8-10 years for 6 grand I'm considering lead-acid (even if it's a <five year life span) if it's ultimately cheaper. If I convert the vehicle, I'll know how to service it.

Another reason I'm asking about lead acid is supply chains. Because most the world's nickel supply comes from Russia, the cost of NiCad and Ni Hydride and nickel containing lithium packs will go up. I'm considering lead because it may be cheaper and easier to acquire in the near future.
Pretty sure if you are in the position to kill a Lithium pack in 8 years, you'll be replacing Lead-Acids every 6 months. How many miles do you drive per year ?

Nobody makes NiCad or NiMh for the industrial applications anymore btw.
 

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Your analysis is completely twisted up. A Leaf has nothing to do with a Metro.

Nickel spot futures have nothing to do with battery costs. Commodities generally rise together...you should be more concerned about copper...

The doors will fall off your Geo long before it'll need a battery changeout. There are also other battery choices. Lead is too heavy and too expensive for an EV...1908 EV technology.
 

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Discussion Starter · #13 ·
So, you want to tear a Metro to shreds?

For your conversion, it doesn't matter DC or AC. The car has low mass so will take off like a scared cat with a DC motor and a 144V battery.

96-144VDC is not generally deadly like the 400V AC stuff is...anyone doing a 400V conversion who's never worked with electricity or on cars, who is not working with someone who has, has a good chance of getting electrocuted. Electrocuted 💀
So then I'll consider DC motor then with adequate specs. I understand there's mortal risks in electricity. I didn't say anything about the voltage of the AC motor. I looked at one guy's geo conversion project, which had a DC motor from a forklift. It had poor acceleration and reached only 45mph.
 

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I was trying to be polite and humble in my inquiry. I stated my lack of knowledge upfront. I really don't appreciate being insulted.
I don't mean to insult anyone and yea, it wasn't aimed at you. Trying to save money by making a DIY EV just isn't a thing but I fully expect a flood of people will try to.

If you are keen to learn about engineering and are prepared to invest in a project over the next few years then good stuff, that is what we are here for. There are much easier ways to save money though. A forklift motor and lead acids is 1990s DIY EVs, heavy, underpowered and very limited range/speed plus a car full of acid should you ever tip it over. A recovered small EV battery and a moderately sized ac motor will make a nice project but not for 15k unless you can get stuff for free and do a lot of the engineering yourself.
 

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Discussion Starter · #15 ·
Your analysis is completely twisted up. A Leaf has nothing to do with a Metro.

Nickel spot futures have nothing to do with battery costs. Commodities generally rise together...you should be more concerned about copper...

The doors will fall off your Geo long before it'll need a battery changeout. There are also other battery choices. Lead is too heavy and too expensive for an EV...1908 EV technology.
Someone told me to consider buying a leaf as opposed to a metro conversion. I was responding to that. I know they're two different vehicles and that one is a ready made ev, where the other is a conversion project.

As for nickel, if most of the supply comes from a country we can't purchase materials from due to blockades and sanctions. the price will certainly go up relative to a resource that have a more broad geological distribution around the world. Titanium is a perfect example of this. During the Cold War, it was very expensive to buy in western nations. In the new cold war, it will be no different.
 

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Discussion Starter · #16 ·
A forklift motor and lead acids is 1990s DIY EVs, heavy, underpowered and very limited range/speed plus a car full of acid should you ever tip it over. A recovered small EV battery and a moderately sized ac motor will make a nice project but not for 15k unless you can get stuff for free and do a lot of the engineering yourself.
I understand. Thanks for filling me in. I appreciate the input.
 

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Someone told me to consider buying a leaf as opposed to a metro conversion. I was responding to that. I know they're two different vehicles and that one is a ready made ev, where the other is a conversion project.

As for nickel, if most of the supply comes from a country we can't purchase materials from due to blockades and sanctions. the price will certainly go up relative to a resource that have a more broad geological distribution around the world. Titanium is a perfect example of this. During the Cold War, it was very expensive to buy in western nations. In the new cold war, it will be no different.
Again, this is not a common knowledge, but there is relatively little Nickel in the Lithium Ion batteries. The estimate is about 28kg in a 60kWh battery pack. So that's roughly 6% by weight.
 

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A DC motor with 20kwh of EV batteries would get you the 60 miles you're looking for at a reasonable price.

Or an AC motor if you'd like regenerative braking and are okay with spending a bit more.

There is zero reason to use lead acid batteries for your project. I wouldn't even consider lead acids for any conversion looking for more than ~15 miles of range. Aftermarket lithium batteries are often not much more expensive than leads either.

Plus the need for frequent replacement with leads as others have mentioned.
 

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As for nickel, if most of the supply comes from a country we can't purchase materials from due to blockades and sanctions.
World production https://en.wikipedia.org/wiki/Nickel#World_production
More than 2.5 million tonnes (t) of nickel per year are estimated to be mined worldwide, with Indonesia (760,000 t), the Philippines (320,000 t), Russia (280,000 t), New Caledonia (200,000 t), Australia (170,000 t) and Canada (150,000 t) being the largest producers as of 2020 Not even a third of world wide production in 2020.
later floyd
 

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"Titanium is a perfect example of this. During the Cold War, it was very expensive to buy in western nations. In the new cold war, it will be no different."

lol..during the cold war, the US bought titanium from...Russia. Despite sanctions, embargos, etc.

The rules only apply to us normal folk. The people that make middle and lower class children fight their wars steal what they want and don't follow rules.

The game in all this Ukraine idiocy is to lift the growth of Western suppliers in commodities and fossil fuels. Nothing else.

A rat will only go for your throat if it's cornered...
 
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