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Planning Lifepo4 battery order, who wants in?

30K views 181 replies 27 participants last post by  JRP3 
#1 · (Edited)
Planning Lifepo4 battery order, who wants in? (Sieden)

Its getting close to putting my money where my mouth is with all this talk of lithium batteries. Testing isn't quite done yet, but I wanted to get the word out early to give plenty of time if anyone else wants in.

I can't give an exact date yet, but its looking like we will place the order for the saturn conversion before the end of the year.

I'll be ordering 45 3.2V 200 AH lithium iron phosphate cells to make up a 144V battery pack for 28.8 KwH's of reserve (and hopefully more than 100 miles of range at freeway speeds).

Please be aware that there is risk involved here, and I was told that the warranty is only 12-18 months even if the battery could in theory last more than 10 years.
 
#6 ·
well, Ill ask the big question first: what kind of money are you talking about? 15K?
The price for my battery will be close to $16000 including BMS and charger. They don't seem to have a problem with an order that small, so your order could be any number you want on top of that. It doesn't have to be 45 cells like mine.

RKM said:
David,

I'm very interested! I think I would be wanting 45 cells 3.2V with 160Ah (if available) for a pack with 23 KWh.

Could you remind us of the discharge C ratings (continuous and max burst) as well as weight per Wh?

Do they provide a suitable charger and BMS for an EV application? Quality and cost?

I'll be very interested to know a cost estimate per Wh. The timing works well for me as I won't need batteries before spring.

Your higher amperage testing of these batteries will let us know how suitable they will be (though the risk remains for long term reliability!:eek:). Thanks again for taking the lead on these batteries.

Rob
I can ask if they offer a 160AH cell (they should), my tests are for 200AH cells though. But The quality SHOULD be the same across the product range.

Constant C is 1C, and max C is 5C (for 15 seconds or less). For your battery, you would have 23.04 kw of power for cruising and 115.1 kw for acceleration (assuming 100% efficiency).

WH/Kg calculates to 88.9 for my 200AH cells (before calculating for charger and BMS). Most of the LiFePo4 like this seem to be between 85 and 100wh/Kg. The older LiPo 3.7V soft cells can be up to 160 wh/kg from what I was able to find. Its been said that the older LiPo technology was good for up to 300 wh/kg in some more general info sources, but I never found a supplier that had anything like that in their product listings. Electrovaya (canadian) claims to have 400wh/kg, but they never returned my Emails.

They do provide a charger matched to the battery if requested. I can only comment on the charger they sent with my 12.8V sample battery which did seem to be of good quality, I had no problems with it. The price for the charger for the 144V battery came to $1503.60. The price for the 12.8V was $128.80.

The cost per WH for just the battery is ~$0.466/wh. BMS and charger are added on top of that. The price quote for my battery works out to $0.55/wh with everything included. Based on this you could now get an idea for what your battery would cost. I do not yet have a price for the freight though.

Yes, there is a risk for the long term, all I can say is that the older LiPo chemistry was good for up to 10 years and LiFePo4 is more stable so maybe it would last longer. But theres no way to be sure so take that into account if you decide to buy.

Higher C tests are comming next......

All prices are in US$

If we could get the price of oil to come back up, that would give the canadian dollar some more strength. Maybe we should all yell "supply shortage!!!!" really really loud at the same time. Thats usually all it took in the past to inflate the price, LOL:p
 
#3 ·
Its getting close to putting my money where my mouth is with all this talk of lithium batteries. Testing isn't quite done yet, but I wanted to get the word out early to give plenty of time if anyone else wants in.

I can't give an exact date yet, but its looking like we will place the order for the saturn conversion before the end of the year.

I'll be ordering 45 3.2V 200 AH lithium iron phosphate cells to make up a 144V battery pack for 28.8 KwH's of reserve (and hopefully more than 100 miles of range at freeway speeds).

Please be aware that there is risk involved here, and I was told that the warranty is only 12-18 months even if the battery could in theory last more than 10 years.
David,

I'm very interested! I think I would be wanting 45 cells 3.2V with 160Ah (if available) for a pack with 23 KWh.

Could you remind us of the discharge C ratings (continuous and max burst) as well as weight per Wh?

Do they provide a suitable charger and BMS for an EV application? Quality and cost?

I'll be very interested to know a cost estimate per Wh. The timing works well for me as I won't need batteries before spring.

Your higher amperage testing of these batteries will let us know how suitable they will be (though the risk remains for long term reliability!:eek:). Thanks again for taking the lead on these batteries.

Rob
 
#4 ·
Its getting close to putting my money where my mouth is with all this talk of lithium batteries. Testing isn't quite done yet, but I wanted to get the word out early to give plenty of time if anyone else wants in.

I can't give an exact date yet, but its looking like we will place the order for the saturn conversion before the end of the year.

I'll be ordering 45 3.2V 200 AH lithium iron phosphate cells to make up a 144V battery pack for 28.8 KwH's of reserve (and hopefully more than 100 miles of range at freeway speeds).

Please be aware that there is risk involved here, and I was told that the warranty is only 12-18 months even if the battery could in theory last more than 10 years.

Need more information.

cylinder cells? good BMS included etc.
 
#7 ·
#5 · (Edited)
Within in the last two weeks I got quotes from both Thundersky and Hipower for $300 per 200 AH cell at quantity of 48, plus shipping.

This price is too high. I have heard that bulk purchasers are getting cells at $.30/ Wh (or about $1/Ah) which would be about $200 per cell. This is only twice the price of lead, so that is encouraging. So look for this kind of pricing and I may consider buying in. For a street size conversion vehicle, this would be 48 cells at about $10K, but giving a range of more than 75 miles.

There are two significant concerns with upgrading from Lead to Li for a full size street vehicle (48 + cells)

1.) There are no available BMS. Without BMS high voltage cell protection on the charging cycle, you run the risk of cooking your cells. There are several people working on solutions (like me), and lots of one-off prototypes but no shrink wrapped solutions.

2.) There are no Lithium prismatic success stories (e.g. thundersky-type block cells). I have heard of serveral people saying that they are in the process of upgrading to Li, then just drop off the earth. What happened to all these attempts? As far as I know there are ZERO operating Li-prismatic street legal vehicles operating in southern California. I don't mind being an early adoptor, but I dont want to repeat mistakes.

Frustrated in CA
Mark.

http://evalbum.austinev.org/1352
 
#8 ·
Within in the last two weeks I got quotes from both Thundersky and Hipower for $300 per 200 AH cell at quantity of 48, plus shipping.

This price is too high. I have heard that bulk purchasers are getting cells at $.30/ wh which would be about $1/Ah which would be about $200 per cell. This is only twice the price of lead, so that is encouraging. So look for this kind of pricing and I may consider buying in.

There are two significant concerns with upgrading from Lead to Li for a full size street vehicle (48 + cells)

1.) There are no available BMS. Without BMS high voltage cell protection on the charging cycle, you run the risk of cooking your cells. There are several people working on solutions (like me), and lots of one-off prototypes but no shrink wrapped solutions.

2.) There are no Lithium prismatic success stories (e.g. thundersky-type block cells). I have heard of serveral people saying that they are in the process of upgrading to Li, then just drop off the earth. What happened to all these attempts? As far as I know there are ZERO operating Li-prismatic street legal vehicles operating in southern California. I don't mind being an early adoptor, but I dont want to repeat mistakes.

Frustrated in CA
Mark.

http://evalbum.austinev.org/1352

I've heard a few more recent stories with the thundersky LFP series, but we are still talking less than 2 years old. You must have high voltage cut off in a specialized charger for lithium as the charge profiles are different between lithium and lead. My sample demonstrated a good ability to gently ballance the 4 cell pack, so I would expect they have such a charger and BMS for a larger battery.

I'm not sure if we can expect $0.30/wh, for this order. Do you know what volume order was required for that price?
 
#9 ·
David,

your test system has BMS integrated into the charger, but for 45 cell order you list BMS and charger separately. Does that mean a different BMS will be used for your 45 cell order? Any details on that BMS?

My understanding is that BMS can be done 2 ways, small modules mounted on each cell which monitor for high voltage cutoff, in this case charger doesn't sense status of each battery, only entire pack voltage. In this scenario each module must pass charging current thru itself in order to keep the rest of the pack charging, which requires powerful components. The other type of BMS senses each cell and adjusts charging voltage per cell, which requires complex charger and lots of wires. So which one will you be getting for 45 cell battery? Or maybe I am completely off base....

BTW, I requested a quote from the EVPST which was mentioned in the other thread here. They have 120AH cells capable of 2C continuous and 4C pulse which is quite sufficient for my EV. Their price is $11610 for 45 cells, plus $2400 for BMS and charger, does not include freight.

Obviously this is yet another company with unproved product, but numbers look pretty good, although you are getting extra 80AH for almost same price.
 
#10 ·
I will ask about the BMS/charger....
 
#15 ·
I have the answer about the charger.

The BMS is indeed built into the charger instead of having the so called "voltage clamper" design that others have used where there is a control chip installed on each cell or module. So the charger takes care of all the battery charge and management issues. Low voltage cutoff is still up you the builder or vehicle operator though.

Emily tells me that the older battery mounted controler was unreliable and was nothing but trouble so they went with the charger mounted BMS instead. Tony told me the same story earlier on.
 
#18 ·
This is unfortunate.

BMS's without low voltage cutoffs and high voltage cutoffs for each cell are dangerous.

that BMS may be better for just 1 cell... but you're planning 48... I'd seriously reconsider.

Looks like my plan to have an EE friend in college design a custom BMS is still the only option.
 
#20 · (Edited)
Is this order just for 200Ah batteries or can we get other configurations? I'd like 90 or 100Ah, but I'd also need 98 of them so my pack total Ah would be comparable to yours. Can this be added to the order (and what would be the cost)? Thanks!
The cost should be the same per watt hour. There doesn't seem to be any savings in perfromance for going with a larger cell. But I'm not sure if the order would be advantagous if there were several different types of cell sizes. I'll have to ask. I did get a price no problem for my battery alone, so anything added on top of that should be OK, just not sure if we would get much of a break.
 
#24 ·
So what you are talking about is simply monitoring each cell, feeding that into a central controler or computer, and then thats where the safety system is engaged to either alert the operator or even automatically cut the power. If any one of the cells gets out of speck the safety system activates.

Metric mind has a BMS system. No idea what the price is though.
http://www.metricmind.com/

I remember swapping a few Emails with a representative for Worley Parsons in Singapore last year. Worley Parsons is a big oil company that operates in Australia, south east asia and indonesia. Anyway, they also have a line of LiPo batteries (the older 3.7V chemistry) and Kokam (in Korea) is making their batteries under license. They carry a BMS system like you describe. One chip on each cell, then all communicate to a main PCM. The price was in the $1.60/watt hour range (before the cost of BMS), so I walked away, but they do have a proven product. ProEV racing is using Kokam batteries in their subaru impreza racer.

So you want to build for the market too? Cool, that makes at least three on the forum so far......:cool:
 
#25 · (Edited)
So you want to build for the market too? Cool, that makes at least three on the forum so far......:cool:
I don't want to, I will... within 8 months... the problem is the time to do it currently because of graduate school.

Metricmind, like all DIY BMS systems, is overpriced. He possesses a product everyone one of us "needs" so he charges accordingly being one of the 2 places you can even find a Lithium ion BMS.

I'm hoping to do a full on 0.09cd (with an cross sectional area roughly 1/3 common sedans), 500lb, all fiberglass aluminum 2 tandum seater in the 11,000 dollar finished range with a 100-120mile range off around 8kwh (with kevlar reinforced sides so no side airbags will be needed)... and/or just sell the prepackaged lithium packs + BMS once I'm to that point. Since my making permanent glass molds and welding jigs for the frame I figured I might as well try to sell a few finished cars since they now would qualify for around 5000 dollars in tax credit with the newest bailout bill :rolleyes:

Anyway that's precisely what I mean about the safety system... the cells could in fact activate shunts from one battery if it gets full and then it can be "reset" once the charging has completed... it's a fairly simple system to be honest, but very effective... also if one cell goes bad (or reaches low voltage before the rest) while driving it can easily just remove that 1 battery from the pack and you can keep driving with almost no additional hardware.

Material science is where my love is at, but it's a hobby so that I don't begin to hate it. Lawyering will be my actual career. But it's bugged me for a long time that the auto industry is so incredibly slow to adapt to anything. There are so many amazing materials well beyond anything that exists now that would take them 100+ years to implement if DIYers/small companies don't start destroying their regional business.
I'm not really talking about fiberglass, elastomers, etc which have been around for 30+ years and they still don't want to implement. But there's things that only exist in lab settings that can easily be scaled up and drop full sedan weights to 700 lbs, provide oil free engines with coefficient of frictions 1/10th that of oil, and provide crash safety at 200+ mph.
 
#26 ·
I know what you mean. Its a big world with lots of good ideas, but it seems like only the bad ones ever see the light of day. I still can't get over the fact that cars and trucks still rust. One of many reasons why I will never buy a new vehicle. Although yours does sounds like fun. You should see what Lexus is planning...neat stuff.

Well Technologic, its our turn now. Maybe we can do better than those that are holding the rest of the world back. "now all I have to do is build it" heehee.:cool:
 
#27 ·
OK back to the original topic.

I got a reply and they do not mind including other sizes of batteries as well and will do what they can to give a good price, but need to know if anyone wants BMS and charger as well. Should I price out everything or just the bare batteries?
 
#28 ·
I'm interested in some 100ah packs... maybe 20 or so....

it will depend entirely on price though
 
#31 ·
Re: Pricing

I’m planning on doing a conversion next year, so I’m studying now. The one conclusion I’ve come to is that to get the range I need to make an EV practical I will have to use some kind of Li-ion technology. I’m thinking something like 144 volts and >150AH. LA just doesn’t have the energy density. So I decided that I have a lot to learn about Lithium batteries and especially battery management systems.

In trying to learn about BMS’s I ran across a man named Peter Perkins who lives in North Yorkshire, England. He is in the process of upgrading his Prius to Li batteries to improve his gas mileage. He is doing the design as an open source project and has put all of the information on a forum on the battery vehicle society. Others on the forum are planning to use his design on EV’s.

Currently the thread is 36 pages long. I think it took me two weeks to read through it all, but I believe it is, or could be, the best BMS available. Of course this isn’t a commercial product. Only a hand full of people have tested it. Plus you will need to have some electronics background to build and customize it. Just from looking around the web, if I were going to implement a BMS today I’d build one of these.

Here’s the link. I’m curious about what you all think.
http://www.batteryvehiclesociety.org.uk//forums/viewtopic.php?t=1245

Larry
 
#37 · (Edited)
In case anyone is interested with the BMS on this thing... this is what it's missing for each cell from what david has said.

http://www.edn.com/archives/1998/091198/pdfs/17d22531.pdf

Something like this cutoff, but designed for 2.5v I believe

Again I know almost nothing about electrical engineering... but that + a high voltage cut off is needed for 100% security on each cell.

This could easily be done if I decide to grab these cells... the problem is I also want my BMS to relay the voltage data from each cell to an LCD which is why I intend to pay someone from my undergraduate college to work something up digitally.

However, that analog circuit would "do the trick" if you used that and a high voltage cut off on the charging system. This is 99% of the "difficulty" of any long range Lion system... and it's so simple :(
 
#38 ·
Update!

The price of the 160Ah battery is confirmed. I have asked Emily for any and all information she can provided on them. As for why the price is different, she mentioned that their pricing is not generally a direct reflection of $ / watt hour like we use but instead varries from different specs, but as for the specific reason why there is a such a big difference, she is not allowed to say (trade secret). I suspect the 200Ah is't used as often and there is a slight premium in price for that size. I've seen similar pricing patterns with TS batteries as well.

Bottom line is, the price was not a mistake. I am seriously considering a switch to 160Ah batteries and simply ordering more of them. I might have to switch to an AC or DC brushless motor though.
 
#39 ·
Have you received any 90Ah price for the same cell voltage? or 100ah pricing?

I'm very interested in a purchase of 20 100Ah or 22 90AH.
 
#46 ·
Electronics like this are well beyond my knowledge, but at this point I think its safe to say that it is possible to make a completely new BMS system if the charger mounted BMS is deemed to be unreliable or if you simply prefer the cell mounted BMS.

We'll have to see how this plays out, but at this point I'm ready to make my order unless theres something weird that I find out about the 160Ah cells. But if anything, they should be even easier to fit in the saturn. I'm thinking of going with 58 160Ah cells for a 185.6V system. Considering the potential savings and higher system voltage, a brushless motor will be used instead of a series wound brushed. The cost of this EV will have to be mostly spent before the end of the year to get the best tax write off for the business, so I can't wait too much longer.

The testing on my sample isn't finished yet, but we're prepared to take the risk based on what I know so far. It will turn over my diesel truck like nobody's business, and thats about the toughest test I can make anyway. I'll still try and take some measurements as time permits but my mind is pretty much made up.

Just waiting on Emily to get back to me with that info.....
 
#50 ·
The testing on my sample isn't finished yet, but we're prepared to take the risk based on what I know so far. It will turn over my diesel truck like nobody's business, and thats about the toughest test I can make anyway. I'll still try and take some measurements as time permits but my mind is pretty much made up.

Just waiting on Emily to get back to me with that info.....
That's fine mate... no issues with me... I'd just rather not have the BMS at all and save the costs :p
 
#48 ·
I was thinking of the MES 250 motor that metric mind carries, but not decided yet. I have a lead on what could be a better one, but I'll have to see. Azure is also said to be working on some better motors, not sure if they'll talk to me though.

Anything with 30HP+ constant and 100HP+ peak power and at least 5000 RPM will be good enough for me. Also expect regen considering the higher price. If worst comes to worst I'll could still go with a warp 9" or something like it.
 
#52 ·
David,

How does it feel to play Santa Claus to so many EV enthusiasts?:D

Again, thanks so much for getting us closer to lithium!

I'm leaning heavily toward the 160 Ah cells, without the charger or BMS. I think I have another supplier for the charger/BMS that I am more comfortable with (no offense!).

Can you quote a price for 90 X 160 Ah cells (I'll be ordering cells for two conversions)?

You're right that our CAD is currently rising! More good news!

Any idea how many KWh are accumulating for this purchase? I expect it may be quite significant. This might be an opportunity to suggest to the supplier that a sale of this size, to a significant number of people could very well make or break their reputation as a supplier of quality LiFePO4 cells. It would be in their best interest to insure that this sale results in very satified customers. Just a thought.

I look forward to hearing what the bare cell price is.

Rob
 
#54 ·
David,

How does it feel to play Santa Claus to so many EV enthusiasts?:D

Again, thanks so much for getting us closer to lithium!

I'm leaning heavily toward the 160 Ah cells, without the charger or BMS. I think I have another supplier for the charger/BMS that I am more comfortable with (no offense!).

Can you quote a price for 90 X 160 Ah cells (I'll be ordering cells for two conversions)?

You're right that our CAD is currently rising! More good news!

Any idea how many KWh are accumulating for this purchase? I expect it may be quite significant. This might be an opportunity to suggest to the supplier that a sale of this size, to a significant number of people could very well make or break their reputation as a supplier of quality LiFePO4 cells. It would be in their best interest to insure that this sale results in very satified customers. Just a thought.

I look forward to hearing what the bare cell price is.

Rob

Well you sure seem confident! 90 160Ah cells? wow

My order (for now at least) will be 58 160Ah cells,

and I think Technologic wants 20 160 Ah cells.

That would bring the total to 86 016 KHW (that s KW - H, not WH!!!) assuming no one else wants to order this time around.

As for feeling like the fat guy in red....I have to say I wasn't really expecting to attract this much attention. If this works out, I might have to launch a formal website. At $0.30 / watt hour this is now a viable option that could put lead out to pasture for good. Add to that the better performance and it could even help the push for more EV conversions. As far as I know, there is no one else that is doing this in canada.

Emily has requested the info from an engineer that I asked for on the 160 Ah cells. I'm waiting on that at the moment.

Now I think I might be getting a little exited....just a little
 
#56 ·
D-oh, you're right. Missing a decimal!

I'll have to look into escrow, because we will have to work something like that out.

I'm open to suggestions on how to perform the transaction.
 
#58 ·
Dude! you cleared 45K a year just trading on your own?

Actually, we HAVE to spend money to avoid paying too much tax. The business will become incorperated in the next couple of days, and that will allow us to claim R&D as a write off. We already have all the materials we need to get through most of next year so we have to spend it on something or else pay the tax on the income.

The problems we have, LOL!
 
#59 ·
The amount of money I've made in the last 4 weeks is up to $7800 dollars from trading GM and a few other stocks (buying and resold 3 times when it's dipped into the 5s... once at 4.80, once at 5.21, once at 5.69. (sold at 7.10, sold at 6.75, still keeping the stock I bought at 5.69)

Good luck to the US... we'll need it to avoid Carter again.
 
#60 ·
I might be in on this deal for BMS & Charger I need
24x 160ahr. (unless 2 chains of 24 can be strung for 76.8v parallel)

Would need a cost

Main issues

1. when are you ordering?
2. I am in the US aka Wisconsin, how is payment going to be handled?
3. Has anyone used lithiums in a car?

Thanx, if I am too late maybe we will have some feedback and I can order next go around.

Cheers
Ryan
 
#61 ·
Hi, rmay635703. Welcome to the forum.

No, you're not really too late. But as I've said to others, I don't think you have to pannic to be in on this purchace. If this goes well, I WILL be doing this again! I'm waiting for the technical specks on the 160Ah cells and unless I find something really wrong there, it shouldn't take too long after that. I hope my saturn conversion will come soon after the batteries arrive and there will be even more info on real world performance to help you decide.

Escrow is one option thats been mentioned for payment, and I'm open to discussing other options. I certainly understand how trust can be a problem having never met face to face. If you have a preferred payment method, then post it here and we can talk about it (or by PM or Email if you prefer a more private chat).

I have heard of lithium batteries being used in other conversions but I don't think anyone of the forum has used them yet, unless my electric trolling motor counts. The other examples I saw used thundersky batteries (LFP series).
 
#62 ·
This does look interesting, but I’m having a little trouble understanding exactly what you will be ordering. That is, what kind of package, etc. Do you have a web site that shows these batteries? I’d like to be able to see a picture and a description so I that think here’s what it is and here’s what it costs per battery.

I might be more interested in a second round because my EV conversion can’t happen until next year sometime. I have the car, but there are a few other things I have to get done first. Does anyone know about shelf life for Lifepo4 batteries?

Larry
 
#64 ·
Does anyone know about shelf life for Lifepo4 batteries?
Larry
Hi Larry,
I'm glad you asked that question. We've been over this before, but I'll post it again in case others don't know.

These batteries have only been in production for about 5 years, so theres no way to know how long they will last. Best projections put the useable lifespan above 10 years, but there is no way to be absolutely sure. Older, more sensitive and less stable LiPo batteries were good for up to 10 years if well cared for, so these should be at least as good. But again, since the technology is only 5 years old, the projected shelf / calender light cannot be absolutely confirmed.

The sample I ordered was only the cells, connector bars and a charger (and related wiring). No case. The website does not show these batteries.

Here is a picture of the 12.8V sample that I ordered and have been testing: What you see is what I got.
 

Attachments

#63 ·
I can do Paypal/escrow/wire transfer directly to the company ... whichever you prefer.

I've had numerous experiences dealing with chinese businesses (and transfering money).
 
#65 ·
I can do Paypal/escrow/wire transfer directly to the company ... whichever you prefer.

I've had numerous experiences dealing with chinese businesses (and transfering money).
I did direct wire transfer as thats what they requested. No real problems, But we recently discovered that our bank has branches in china for decades, so we might be able to streamline it a little better. Escrow is OK, but theres a fee that would bring the cost up a bit.
 
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