Sourcing Li-Ions from China (or NiMH for that matter)

[terry.kane]

I've been reading on the EVDL about those intrepid pioneers out there who have tried to source batteries from the myriad of Chinese manufacturing companies cropping up.  It appears that things are moving quickly on this front in China and I think it's an opportunity to "get in on the ground floor".

Most of the issues lamented on EVDL have been regarding the logistics of buying from China directly.  I think I can get around this issue because my company has people "on the ground" in China and we ship 2-3 full sea containers every day of freight bound for the US.  All that would remain would be financing.

I have sent emails to a couple of the manufacturers I found on Alibaba.com regarding their willingness to sell small R&D-scale quantities of Li-Ion or NiMH (high power) batteries.  In reality, it might be better to find the best manufacturer with the best reputation for quality and consistency and try to arrange a representation deal. 

I envision starting a new division of my company or a new company to do this.   If we could convince them that one possible path to market is to reach the hobbyists and small EV companies, we could become their foothold in the N. American market.  I'd hope to start out with a large "consignment" inventory, partially funded by the manufacturer.  Todd Dore mentioned quality issues with Chinese Li-Ion cells but I think the inventory could serve as a warranty replacement stock.  We could support their learning curve with feedback on performance and reliability.  Best of all - those involved would get batteries!

At least one of the manufacturers I found also makes chargers and mentions battery management systems.  I'd call them the front-runner, assuming they are interested.  I think the way to get enough credibility for the Chinese Mfr. to take us seriously would be to put together a "board of directors" with a sufficient cirriculum vitae in the field.  I believe I could convince my boss to be involved and to lend the additional credibility of GMT's international business reputation.

If anyone is interested in participating and has something substantive to contribute to such an effort, please contact me.

-Terry Kane

[terry.kane]

I received the following very prompt reply to an inquiry for their large, 90Ah 3V Li-Ion motive power cell: US$ 178 each!
So for a 120V nominal pack, cost without freight, duty, etc. would be 40 x $178 = $7,120 @ 264 pounds!  For the 40 Ah units, it's $118 each ($4,720 @ 220Lb).  As stated above, I believe I could get my company's logistics dept. to handle the transaction and might even throw in the freight, as this pack would not even wiggle the needle on a sea container, from a cost or weight standpoint.

This links to the description of this power cell: http://www.thunder-sky.com/products_en.asp?fid=66&fid2=70

Dear Terry,
 
Thanks for our message.
we can offer the Li-ion battery which is as your requiry and this is the detail information of our item for your reference.
3V 90AH Li-Ion power battery - 40 each     
PRODUCTS MODEL ： TS-LFP90AHA
Nominal Capacity  ：90AH
Operating Voltage：2.5V～4.25V
weight：3kg±100g
Dimensions：145×220×68（mm）
Price:Fob Guangdong  USD178/PC

3V 60AH Li-Ion power battery - 40 each     
PRODUCTS MODEL ： TS-LFP60AHA
Nominal Capacity  ：60AH
Operating Voltage：2.5V～4.25V
weight：2.5kg±100g
Dimensions：115×215×61（mm）
Price:Fob Guangdong  USD118/PC
 
If you have any other request welcome to contact with me.

Best regards
maggie
 
Ningbo Thunder Sky Green Power Sources Co., Ltd.
www.thunder-sky.cn
tel:0574-62655560
fax:0574-62655562

[bruce.lanzerotti]

Terry,
Please call me @ 630-865-5134. I very interested in this situation.
Bruce Lanzerotti

[todd.dore]

Looks like you may try to do business with Thunder-Sky.  They have had major quality issues in the past - hopefully that is cleared up by now.  What about the charging and  BMS?

Rich Rudman is running the TS LFPs in a new PHEV that he's done.  I'm not sure how much he's driving it to get any meaningful data.  He's modified his charger and regs to go with the TS batteries.  He is Manzanita Micro.

Keep in mind a good BMS will add $2k or so to the cost, so we're getting close to $10k for a battery pack.  Sounds a bit steep.

By the way, I belong to a Thunder-Sky yahoo group and have been watching the traffic on these for over 3 years now.

-Todd

[ted.lowe]

Interesting discussion!  Let's compare lead acid vs TS Li using my S10 as an example.

i have 20 * Trojan T-125 6v batteries = 120v nominal.  From the trojan spec sheet:

http://www.fveaa.org/fb/trojan-battery-product-specs-guide.pdf

the T-125 has a 20hr rating of 240ah and 132 minutes at 75a.

From their spec sheet, i don't understand how TS rates their 90ah battery:

http://www.thunder-sky.com/pdf/TS-LFP90.pdf

ie, what is 0.3CA  or 3CA ?  Is that the nominal steady state discharge current (for the 90ah rating)?  How does it compare to the T-125?

i suspect to build a pack with the same range as my S10's T-125 pack out of the 90ah TS, i would need about 2.5 strings of 40 cells.  (240 / 90 with a discount for the TS's lighter weight). It would certainly be lighter and smaller, but would cost about $17.8k.  Definitely cheaper then the $30k i calculated last time i ran the numbers.   

Now let's look at the lifetime issue as it relates to cost over time.  The number of cycles (to 75% dod) is generally quoted around 350 for the T-125 but > 2500 for the TS.  So assuming the TS lasts that long (could be risky based on what i've heard), the TS pack would last about 7 times longer than the T-125's.  Say the T-125 pack costs $2000 and 7 such packs would cost $14k.

The TS costs are just for the batteries; there will be a substantial cost for BMS and charger.

So the TS's are lighter, smaller, but more expensive per mile with a higher risk of premature failure with significantly more complex electronics/connections/etc.

Someone please check/challenge my understandings/calculations/etc.!!!

If the above is roughly correct, then i'm still not getting my pack of Li bats for Christmas this year 

[ted.sanders]

Terry,

There is a man by the namee of Jukkw Jarvinen on the EVDL list who has been testing some ThunderSky lithium batteries.  I think he has be running a car for about two years on these batteries.  If I am not mistaken he is a dealer in Norway.  He might be able to give you some more information on working with Thunder Sky.

[terry.kane]

Thanks to everyone for your interest and comments.  I will try to follow-up on all of this as soon as I have some time!

I did receive another answer from a different China manufacturer: Zhejiang Headway.  They have cylindrical-shaped LiFePO4 cells - the largest rated at 3.2V & 10Ah.  They quoted me about US$19 per cell, Ex-Works (Shanghai) which includes VAT (duty).  If my company covers or at least "eases" the freight, it shouldn't cost us any more than $20 per cell, landed in Chicago after all the transaction fees, etc.  Their minimum order quantity is 1,000 pieces so we're talking about up-front costs of $19,000. 

This would be for, essentially, 10,000 Ah of 3V storage capacity.  I'm still shaky on the math here so bear with me:  10kAh at 3V = 2.5kAh at 12V or 250Ah at 120V?  That means you'd need nearly all 1,000 cells to equal one 120V pack of T-125s?  Is this correct?  If so - it's a total non-starter.  Another way to look at it: 40 cells @ 3V @ 10Ah = 120V @ 10Ah.  240 Ah/10Ah = 24 strings.  24 x 40 = 960 cells.  Comes out the same.  I'm getting discouraged but I'm not sure I'm looking at this all correctly.

I read in an old newsletter about Ryan Brandys battery calculators - did these ever get finished and are they available to us?  Looks like he's no longer an active member.  Can anyone comment?

[terry.kane]

I've been in communication with Thunder Sky since I started this thread and they have been pretty responsive.  Thanks to Todd Dore I joined the Thunder Sky Yahoo group and have been learning a lot there too.  Jukka Jarvinen is active on the discussion board.

I received the following reply to my inquiry about their BMS:

Dear Terry,
 
Thanks for your email.
we can offer you the information on a proper battery management system but you should tell us the following points.
1.how many battery you will use?
2. the position for the batteries to place.(you'd better offer pic to us)
3.each battery pack's comparative position so that we can make the correct length of the connect wire.
 
Attachment is technology data and price for BMS.
 
Best regards

Maggie Huang <maggienb@yahoo.com>

Here is the quote and a photo of the components:
http://www.fveaa.org/fb/ThunderLiIonbms_Qt_189.doc
http://www.fveaa.org/fb/ThunderSky_LiIonBMS_190.jpg

I haven't had time to look this over in detail so I'm not sure how much a BMS to cover 40 or 80 cells to make a 120V or 120V (buddy pairs) pack would cost.

[todd.dore]

Terry:

So how much would the BMS be for your needs?  Also, can you get a price quote on their LCP and LFP cells?  (I'm thinking about the 100 Ah, 150 Ah, and 200 Ah batteries).

I think Jukka would make a BMS for you for the right price.  There's also someone in the UK who would do one (Jukka is in Finland).  Finally, here in the US, Metric Minds (Cedric) might make one for you and Manzanita Micro (Rich) has mentioned that he can now produce battery regs for the Li-ion batts (Thunder Sky) that work with his PFC chargers.  Don't know how much he would charge for them - maybe $75 a pop or so.  Of course, his charger is about $2k as well, so a BMS from him would be pricey.