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I’d like to add batteries from a used Leaf battery pack to a ‘74 VW Beetle (Bug) conversion that has dead lead acid batteries. First, the background:

About six years ago I finished an EV conversion. The forum guidance was very helpful! It took me about six months of weekends to finish the project. The lead acid batteries provided good service in the Bug for about three years of the 10-mile round-trips traveled six days a week ... and then the batteries died. The ‘74 Beetle EV has been sitting in the driveway for about two years.

Next phase – bought a used Leaf. In the three years of service the battery pack condition dropped from ten to five bars. Like the Bug, it served my family well … until it was totaled last weekend.

I have not received an insurance assessment yet, but similar 2013 Leafs with 80K miles are going for $5k - $7K. There is a $500 deductible on the policy. The insurance company expects about 20% of the assessment value to be recouped by the salvage value. If I keep the Leaf, the insurance company will pay 80% of the assessed value. Therefore, the batteries will cost me (or reduce the insurance payment by) about $1.2K.

I am reaching out to the collective expertise of the forum again to help me with my decision … and thank you in advance!
 

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I'd keep the batteries. $1300 even for weak batteries is cheaper than anything else you'll be able to find.

Insurance is funny. I've had two writeoffs. One company said their policy is a flat 10%. The next company said their policy is a flat 40%.

For a writeoff of an old vehicle, with a salvage brand on it, expecting 40% of the market price is absolutely absurd. 10% is fair. 20% is pushing it.

There may be some room for negotiation.

The way it works here, there are laws restricting how the insurance companies can operate. They are not allowed to just make an exception for someone. They can create a rule that applies to everyone, or change a rule, but they can't just do something differently for them.

That means that insurance companies have a billion adjustment rules, and they just choose not to apply those rules most of the time. You have to point things out or ask specifically for them, and make them agree that they apply, and then they can apply their rule.

For example, if you have rental coverage as part of your policy, to get you a vehicle to drive while yours is being repaired, and you don't opt to actually use that, that has value to them (insurance not having to rent you a car). It won't affect your settlement offer though. But if you point it out and ask for it to be considered, and they agree, they will apply their "didn't use rental coverage" rule and increase your settlement amount.

Anyway, point being, that 20% might not be perfectly rigid. But who knows what the precise reasoning to get it to change might be, or what words you'd have to use, or whether they'll just stonewall you regardless.
 

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Discussion Starter #3
My Bug is built around 96V lead acid batteries with the following main components:
Kilovac EV200 Series Contactor
D&D Motor ES-31C
Sure Power 71030i DC-DC Converter (96V)
Curtis PMC 1231C
Zivan NG1 Charger (96V)

Assuming I go with 144V system, I assume I have to replace the charger and converter and add a BMS.

Knowing that I have a steep learning curve in front of me, let me ask: What components from the wrecked Leaf, other than the batteries, should I keep?

... and, is there a conversion in the forums that comes to your mind that would be representative to my project?
 

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It's tempting to think about splitting the laef pack 4 ways to get back down to the 96 V region of the original setup. Then you could re-use the charger and dc-dc converter, basically everything, and have a much longer range.

The kicker is how to parallel 4 strings safely. The best i've seen has been Wolftronix approach to add contactors for each string. And you would need some sort of BMS to monitor and balance the cells.

good luck and keep safe.
 

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The easy solution is, don't parallel 4 strings. Leaf cells are individually accessible. Just string 4 of each into a parallel block, then connect those in series.

Nothing extra is needed.
I agree. The Leaf pack is unusual in having such small modules (only 2S), with a substantial terminal for access to the intermediate point (compared to the tiny connection usually provided for BMS access); that makes them unusually easy to parallel at the lowest level, avoiding parallel strings.


Various configuration strategies are available, including connecting sets of three modules in parallel for a nominally 120 V pack with the full Leaf capacity, or choosing the best 40 of the 48 modules and connecting them in sets of two modules in parallel for a nominally 150 V pack with 83% of the full Leaf capacity. A lot of this will depend on space available for the battery pack.
 

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Knowing that I have a steep learning curve in front of me, let me ask: What components from the wrecked Leaf, other than the batteries, should I keep?
at least the whole Drive Unit with axles, charge port, gas padle, maybe brake system.
Charger / DCDC are included in the Drive Unit stack btw.

Also, don't pin yourself on the Leaf battery:
-when size doesn't work well in your beatle
-when capacity is t degraded
-etc.

in other words: keep an eye out for other batteries also, you can always sell the leaf pack.
 

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I’d like to add batteries from a used Leaf battery pack to a ‘74 VW Beetle (Bug) conversion that has dead lead acid batteries. First, the background:

About six years ago I finished an EV conversion. The forum guidance was very helpful! It took me about six months of weekends to finish the project. The lead acid batteries provided good service in the Bug for about three years of the 10-mile round-trips traveled six days a week ... and then the batteries died. The ‘74 Beetle EV has been sitting in the driveway for about two years.

Next phase – bought a used Leaf. In the three years of service the battery pack condition dropped from ten to five bars. Like the Bug, it served my family well … until it was totaled last weekend.

I have not received an insurance assessment yet, but similar 2013 Leafs with 80K miles are going for $5k - $7K. There is a $500 deductible on the policy. The insurance company expects about 20% of the assessment value to be recouped by the salvage value. If I keep the Leaf, the insurance company will pay 80% of the assessed value. Therefore, the batteries will cost me (or reduce the insurance payment by) about $1.2K.

I am reaching out to the collective expertise of the forum again to help me with my decision … and thank you in advance!
You can revive the Beetle with Leaf Modules but you want to be sure you have the newer Lizard modules. They are much better at handling heat and the cells last longer and easier to use than the old sardine can Leaf Modules. I have some of both. You should be able to buy a complete Newer Pack with better capacity for the same price you are quoting. The ones you are talking about might be good for a battery back up system for your home. Im using mine in a 48volt pack arrangement for our backup system for the house.

Im not so keen on the D&D motor but if it has served you well then I'd keep it. The rest sounds fine.

Shop around for the modules but if your range is still 10 miles then the used ones from your wrecked module should do. Sounds like a lot of money for modules with 1/2 capacity. Capacity is not much to begin with.
 

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Coming from lead acid driving 10 miles on a charge...

Yank out the old batteries, fill the space with however many Leaf modules fit easily or until you reach the desired voltage. A dozen Leaf modules gets you 90V and will get the car 10 miles, even tired.

I feel like the trickiest bit will be installing a BMS.
 

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I would encourage NOT dissecting a used battery pack from a Leaf, or anything else, that was intended to run an AC motor at 300+ volts. You would have to completely pull apart and re-configure parrallel/serial connections to get appropriate voltage and ah to use with a DC motor/controller. Second, why would you put all the time in to reconfigure a used pack that you KNOW is failing?

I would suggest you shop for large format prismatic LiFePO4 cells (CALB or similar), 100+ah per cell, and do a simple series pack. Since you are going to have to change the charge curve in charger anyway, upgrade to at least 120v nominal and you will be thrilled with performance.
 

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I would encourage NOT dissecting a used battery pack from a Leaf, or anything else, that was intended to run an AC motor at 300+ volts. You would have to completely pull apart and re-configure parrallel/serial connections to get appropriate voltage and ah to use with a DC motor/controller. Second, why would you put all the time in to reconfigure a used pack that you KNOW is failing?

I would suggest you shop for large format prismatic LiFePO4 cells (CALB or similar), 100+ah per cell, and do a simple series pack. Since you are going to have to change the charge curve in charger anyway, upgrade to at least 120v nominal and you will be thrilled with performance.
Is this true? Leaf modules come in 48 nicely isolated 7.5v air-cooled modules that are easy to reconfigure any which way, and I've never seen cheaper batteries anywhere.
 

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I would encourage NOT dissecting a used battery pack from a Leaf, or anything else, that was intended to run an AC motor at 300+ volts. You would have to completely pull apart and re-configure parrallel/serial connections to get appropriate voltage and ah to use with a DC motor/controller. Second, why would you put all the time in to reconfigure a used pack that you KNOW is failing?

I would suggest you shop for large format prismatic LiFePO4 cells (CALB or similar), 100+ah per cell, and do a simple series pack. Since you are going to have to change the charge curve in charger anyway, upgrade to at least 120v nominal and you will be thrilled with performance.
All true
IF you want to spend twice as much for cells with a fraction of the life and a massively higher failure rate

And then there are sensible people who will use modules from production EV's
 

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Leaf modules comes in 48 nicely isolated 7.5v air-cooled modules that are easy to reconfigure any which way...
That's my thinking, too. The Leaf modules are generally similar in shape to LFP prismatics, mount the same way (in clamped stacks), have similar terminals, similarly require no cooling system, work with the same BMS design... and less than half as many are needed. Even if they need to be paralleled to hit the target capacity, they are easily paralleled at the cell level so there are no management implications, with no more complex wiring than connecting twice as many individual LFP cells.

I will note that all but the earliest Leaf modules are bonded in pairs, limiting their physical arrangement.
 

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All true. IF you want to spend twice as much for cells with a fraction of the life and a massively higher failure rate
Not to sound like a broken record, but I'll toss my hat in the ring along (almost) everyone else and reitterate the Leaf cells are probably the easiest cells to configure and that it's a complete non-issue.

And further, that LiFePO4 cells have never *not* had problems on people's vehicles (100% failure rate of at least one of them), are astronomically more expensive, and provide no other benefit.

Using large prismatic LiFePO4s was perhaps good advice 12 years ago, it is very poor advice today.
 

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Thank you for your advise. I too am switching from lead acid to Lithium.
Post lately are about salvage Leif packs or building a Tesla pack.

The complexity makes me uncomfortable. I guess there is good and bad
about any pack so I was glad to hear a few good words about earlier technology.


Has anyone been happy enough with their early lithium pack and BMS that they would purchase the same again. That says a lot and would help me.
What do you have?

Thanks, James
 

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I've been using Thunderstruck charger, charge controller, and BMS, and I'm happy with them. The documentation is fantastic, and the components work well.

I've only done a few charge cycles without the car being on the road, but it behaves as desired. I see people using the Orion BMS as well.
 
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