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Discussion Starter · #1 ·
I've posted a few times on this forum and received very valuable feed back but now it's time for the rubber to meet the road as it were.

I purchased a 1959 Austin Healey Sprite a few weeks ago, which was converted to EV in 2005. It has a MES-DEA TIM600, matched to a MES-DEA 200-175 motor. I have finally acquired the TIM software (thanks to [email protected]!) so am already further than I thought I'd be.

The problem is that I know nothing about how the car was built, no schematics, nothing. The original lead acid batteries are dead, and only provided a 25 mile range when new so that's gotta change. I'm sort of flying blind here. To further complicate things, I'm brand new to EV... I wasn't really looking for an electric Sprite, just a Sprite. So I don't have much background knowledge in this field. I'm a DIY techno-geek so am pretty sure I can come up to speed but don't want to reinvent the wheel.

I've heard that MES-DEA can be hard to work with which has me worried. For example, even with the manual, I don't know exactly how to power up the TIM to even see if it's functional!

I'm prepared to throw some money at this project because the idea of an electric Sprite excites me. So my question to the community: Should just rip out everything and go with newer hardware which is easier to work with, or stick with the MES-DEA setup and see what happens?

Thanks for your thoughts,
Mark
 

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I can't see any sense in starting from scratch if you only need a new battery pack. If you were to start from scratch, you might be better off with a stock vehicle than with someone else's undocumented conversion.

Even though nothing may be working due to dead batteries, you can still understand what you have. For instance, just look at what voltage each battery has (if they have fill caps there's a cap per cell and each cell is two volts) and follow the wiring to see how many are connected in series to determine the nominal battery voltage.
 

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Discussion Starter · #3 ·
Thanks Brian,

I appreciate the input!

I have the original battery configuration of 29 6V motorcycle batteries which I believe were in series. But I'm not looking to replace the existing config as it only had a ~25 mile range. I'd really like to update to newer tech to improve the range.

If I'm reading the documentation correctly, I think I just have to input the minimum and maximum voltage of the new battery pack(s) even if it's a different chemical mix.

But the car itself is a mess! The engine bay is very well laid out but under the dash is a rats nest of wires and there are multiple unlabeled switches on the dash that do... something?

I think the cheapest and quickest option is to hire an EE to map out all of the wiring so I know what the heck is going on.

But the real question remains: Is the current hardware/motor sufficient to provide proper power and range to make it worth keeping. Is the motor capable of reasonable accelleration? I'm not looking for Tesla's ludicrous speed mode, but I would like to drive around town like a regular car, not like a moped. ;) I'm also not looking for a 300 mile range. I think 50 miles would be perfect for my needs.
 

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If in series, you are looking probably at an 180v controller. It won't care what type of battery is powering it. That's a reasonable voltage to hit with li-ion cell packs from other EVs. You will need a new charger and BMS to control those packs though. 50 miles should be quite reasonable for this upgrade.
 

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Discussion Starter · #5 ·
Awesome, thanks hallkbrdz!

I'm not sure what the charger and BMS are on this car though. There are a couple of grey boxes with loooots of electronics in them. They appear to be custom made so where do I start with replacing them.

I have some photos in my google drive for this project which have pics of these two boxes:

Please keep in mind that I'm a noob at this so not exactly sure where all of the parts fit in. If there is a EV 101 track that will help avoid dumb questions like this I'm all ears. :)

Thanks!
Mark
 

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I'll throw my hat in with "Replace the batteries with lithiums and find out if it works".

You can probably get a cheap Prius battery pack. They're worthless for use (NiMH, bulky, and awful energy density), but a single pack is high enough voltage and small, they'll provide enough to test with (a minute or two) and you can get them cheap or free. Use that rather than buying new lead acids just to test.

You don't need to hire an EE to map it out. You can follow wires and make a diagram of what goes where. It's probably not complicated, probably obvious what everything is for. Pay someone to run the last mile for you if need be, but do the gruntwork for them.

It's highly unlikely anything is wrong with the motor or controller. Lead acids die and aren't worth replacing, and then the car sits. That's probably what happened in your case.
 

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Awesome, thanks hallkbrdz!

I'm not sure what the charger and BMS are on this car though. There are a couple of grey boxes with loooots of electronics in them. They appear to be custom made so where do I start with replacing them.

I have some photos in my google drive for this project which have pics of these two boxes:

Please keep in mind that I'm a noob at this so not exactly sure where all of the parts fit in. If there is a EV 101 track that will help avoid dumb questions like this I'm all ears. :)

Thanks!
Mark
I'm going to echo what everyone else is saying and get a lithium battery pack. The old lead-acid batteries probably don't have a BMS as they aren't needed with lead-acids. Lithium batteries definitely need a BMS for both safety and longevity. Your options really depend on budget.

  • High end - 7 Tesla modules in series ($10K)
  • Mid end - Nissan leaf batteries ($5k)
  • Low end - batteries from a hybrid (cheap)
I wouldn't recommend tinkering with the gray boxes yet. They're likely boxes for contactors, fuses, etc. and are more likely than not in good working condition.
 

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Discussion Starter · #8 ·
Thanks all, this is exactly the kind of advice I'm looking for!

So, I'm guessing that depending on what battery type/brand I buy will determine the charger and BMS I need?

Replacing the lead-acid batteries was never really on the table unless they've gotten exponentially better in the past 15 years. The original setup only had a range of 25 miles and I believe that was a generous estimate. I think the only reason I would toy with replacing them is that it would require the least amount of retrofitting, but I don't think it's worth it.

If I try to find a cheap/free Prius pack for testing, I would then have to buy a charger for it I'm sure, but since I won't be driving it using this pack, will I need a BMS?

Thanks again,
Mark
 

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Thanks all, this is exactly the kind of advice I'm looking for!

So, I'm guessing that depending on what battery type/brand I buy will determine the charger and BMS I need?

Replacing the lead-acid batteries was never really on the table unless they've gotten exponentially better in the past 15 years. The original setup only had a range of 25 miles and I believe that was a generous estimate. I think the only reason I would toy with replacing them is that it would require the least amount of retrofitting, but I don't think it's worth it.

If I try to find a cheap/free Prius pack for testing, I would then have to buy a charger for it I'm sure, but since I won't be driving it using this pack, will I need a BMS?

Thanks again,
Mark
You will need a charger, but that same charger can be used with any battery. Chargers just convert AC power from the wall to the right DC voltage.

A BMS isn't necessary if you're strictly testing, just be careful and don't let them charge to above the designed voltage.

Sent from my GM1917 using Tapatalk
 

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I think the cheapest and quickest option is to hire an EE to map out all of the wiring so I know what the heck is going on.
I don't think you're going to want to pay an electrical engineer to do that. Almost anyone is likely to tell you that it would be cheaper and safer to rip it all out and pay for a new design instead... and I doubt that you want to pay for that, either. If you can find another amateur in your area who is willing to help you because the project is interesting, you could work with them and learn about the system as he/she figures it out.
 

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But the car itself is a mess! The engine bay is very well laid out but under the dash is a rats nest of wires and there are multiple unlabeled switches on the dash that do... something?
Unfortunately, that's roughly how Austin built them. :LOL: After years of working on more modern vehicles, I was interested to note how much our Triumph Spitfire's wiring looks like a homebuilt project... done by someone who only had spools of wire available in four colours. But there is likely an original factory wiring diagram available, and you might find that most of the wires are in the original Austin diagram.
 

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But the real question remains: Is the current hardware/motor sufficient to provide proper power and range to make it worth keeping. Is the motor capable of reasonable accelleration? I'm not looking for Tesla's ludicrous speed mode, but I would like to drive around town like a regular car, not like a moped. ;) I'm also not looking for a 300 mile range. I think 50 miles would be perfect for my needs.
I don't really know anything about the MES-DEA products, but for others I'll note that there is some detail in the earlier thread on this car, and in a product line datasheet.

21 kW is not much, even for a Sprite, but the motor and controller are likely efficient enough that they are not a concern for range - that's a battery issue.
 

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Discussion Starter · #13 ·
Thanks guys!

reiderM, I'm guessing there are better and worse chargers and BMSs out there. Is there one that DIY EV'ers lean toward? I'm also guessing it has to have the correct connection for whichever battery pack you have?

brian_, Heh, yep, I've had an MGB and a TR6 and recall no end to electrical problems. My British auto mechanic buddy said that Lucas Electronics was commonly referred to as 'the prince of darkness'.

I managed to get the hood off today thanks to a couple buddies, thing weighs close to 100 pounds! Now have much better access to the engine bay so am feeling more confident about figuring this mess out. Kinda hard to strike up new friendships right now with C-19 and all but will look around for a local group. I'm outside of Denver so shouldn't be too hard.

Looks lik the MES-DEA motors topped out at 30 kW, In an ideal world, what motor would suite that car? Doesn't need to race... but that would be fun too. ;)
 

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Discussion Starter · #14 ·
You will need a charger, but that same charger can be used with any battery. Chargers just convert AC power from the wall to the right DC voltage.

A BMS isn't necessary if you're strictly testing, just be careful and don't let them charge to above the designed voltage.

Sent from my GM1917 using Tapatalk
I replied to two people at once, but I think I need to respond to you individually so you'll get notification of my response so I'll break it out:

I'm guessing there are better and worse chargers and BMSs out there. Is there one that DIY EV'ers lean toward? I'm also guessing it has to have the correct connection for whichever battery pack you have?
 

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Discussion Starter · #15 ·
I don't really know anything about the MES-DEA products, but for others I'll note that there is some detail in the earlier thread on this car, and in a product line datasheet.

21 kW is not much, even for a Sprite, but the motor and controller are likely efficient enough that they are not a concern for range - that's a battery issue.
I replied to two people at once, but I think I need to respond to you individually so you'll get notification of my response so I'll break it out:

Heh, yep, I've had an MGB and a TR6 and recall no end to electrical problems. My British auto mechanic buddy said that Lucas Electronics was commonly referred to as 'the prince of darkness'.

I managed to get the hood off today thanks to a couple buddies, thing weighs close to 100 pounds! Now have much better access to the engine bay so am feeling more confident about figuring this mess out. Kinda hard to strike up new friendships right now with C-19 and all but will look around for a local group. I'm outside of Denver so shouldn't be too hard.

Looks lik the MES-DEA motors topped out at 30 kW, In an ideal world, what motor would suite that car? Doesn't need to race... but that would be fun too.
 

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Discussion Starter · #16 ·
I'll throw my hat in with "Replace the batteries with lithiums and find out if it works".

You can probably get a cheap Prius battery pack. They're worthless for use (NiMH, bulky, and awful energy density), but a single pack is high enough voltage and small, they'll provide enough to test with (a minute or two) and you can get them cheap or free. Use that rather than buying new lead acids just to test.

You don't need to hire an EE to map it out. You can follow wires and make a diagram of what goes where. It's probably not complicated, probably obvious what everything is for. Pay someone to run the last mile for you if need be, but do the gruntwork for them.

It's highly unlikely anything is wrong with the motor or controller. Lead acids die and aren't worth replacing, and then the car sits. That's probably what happened in your case.
Hey Mat, so I find a lot of cheap Prius NIMH batteries on Ebay, which range between 7 & 8 volts, how many of these bad boys do I need to get something that'll work?

Thanks!
Mark
 

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Hey Mat, so I find a lot of cheap Prius NIMH batteries on Ebay, which range between 7 & 8 volts, how many of these bad boys do I need to get something that'll work?

Thanks!
Mark
Hey, unless you can get a complete prius battery pack for free (Matt will tell you this is easy, but he would tell you the same thing about building your own rocketship :)) then a prius NiMH pack is a dead end suggestion.

Basically, the car does not care what is producing the voltage, you just need to get to the right voltage. You said it originally had 29x 6v lead acid batteries - so you need 29x6 = 174ish volts. It does not have to be exact. So to get back up to 174v with 7.2v NiMH modules, you would need 24 of them. The problem is that those modules only have 6.5Ah, i.e. they can only put out 6.5 Amps for 1 hour. So your battery will be way too small to do anything but the most basic testing. You would have a little over 1 kwh of energy, so you might move a tiny little car 4 miles with that battery. The top speed would be miserably, probably a jogging pace, or you would blow out the cells by pulling too much juice out of them.

In short, spending 400-800 bucks on that would be silly. If you found a free one, sure. But if you can sell it on E-bay for 700 bucks, who would give it away for free?

I suggest you hop on Wikipedia and read up on batteries. All sorts of batteries. Follow up on all the terms you have never heard of. Get a basic grasp of the science, and you will figure out what questions you really need to be asking. There are a lot of very smart and very informative people on this forum that can help you, but you will need to know which questions to ask. Anyway, hope I have not come off as a complete curmudgeon, I hope you will have success (and that you will post some pictures of batteries).
 

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Discussion Starter · #18 ·
Hey, unless you can get a complete prius battery pack for free (Matt will tell you this is easy, but he would tell you the same thing about building your own rocketship :)) then a prius NiMH pack is a dead end suggestion.

Basically, the car does not care what is producing the voltage, you just need to get to the right voltage. You said it originally had 29x 6v lead acid batteries - so you need 29x6 = 174ish volts. It does not have to be exact. So to get back up to 174v with 7.2v NiMH modules, you would need 24 of them. The problem is that those modules only have 6.5Ah, i.e. they can only put out 6.5 Amps for 1 hour. So your battery will be way too small to do anything but the most basic testing. You would have a little over 1 kwh of energy, so you might move a tiny little car 4 miles with that battery. The top speed would be miserably, probably a jogging pace, or you would blow out the cells by pulling too much juice out of them.

In short, spending 400-800 bucks on that would be silly. If you found a free one, sure. But if you can sell it on E-bay for 700 bucks, who would give it away for free?

I suggest you hop on Wikipedia and read up on batteries. All sorts of batteries. Follow up on all the terms you have never heard of. Get a basic grasp of the science, and you will figure out what questions you really need to be asking. There are a lot of very smart and very informative people on this forum that can help you, but you will need to know which questions to ask. Anyway, hope I have not come off as a complete curmudgeon, I hope you will have success (and that you will post some pictures of batteries).
NO! This is exactly what I'm looking for, thanks to you and everyone who has chimed in! I have no idea what I'm doing and really hate asking stupid questions. This is EV 101! However, one more stupid question if you don't mind. Can you give me a clue as to what to search for on Wikipedia so I don't go down the wrong rabbit hole? Getting up to speed is a lot quicker is there are no off-ramps. ;)

Thanks,
Mark
 

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You can start with this. It will be full of links, so if you are a little fuzzy on what an Ampere-hour is, follow the link and get a refresher. When you finish with that, you will probably have more questions than you started with. Google those, and search wikipedia some more. Then google your motor. You probably dont have a BMS, but you will need to learn about that. Watch videos on youtube. Go to websites selling EV conversion parts and download the product manuals. Read those, they are full of useful info. Starting from zero, you should probably plan on doing a hundred hours of reading or so. If it is not fun, then you have picked the wrong hobby, and you should maybe start over with something else :)
 
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