Re: Lithium battery manufacturer question

[EZgo]

Has anybody ever heard of or used batteries from Qinhuangdao Xinchi Photoelectricity Technology Co.,Ltd.?http://xinchibattery.zxq.net/ebikebattery.html ?

With the help of this forum I have narrowed my search for a small purchase of 10 Lifepo4 battery Packs down to a small handful of suppliers. (See previous thread in Battery technology, LiNiMnCo versus lifepo4 from USA or China.) That said, for the last 6 months I have been in communication with Carl from Qinhuangdao Xinchi Photoelectricity Technology. His communication has been first-rate & he has answered every question I have asked promptly & to my satisfaction. They have a good web-site but do not take orders on-line. Carl would send me a sales contract or Proforma Invoice & I would pay by TT or Western Union.

On paper their specs are as good or better than any of the Lifepo4 vendors that have been recommended to me but I can not find any independent reviews. They have been in business since 2006 & they defiinantly a legitimate company.

A 36V10AH Lifepo4 battery pack is $200 & includes a 2 amp charger & BMS. (They build the BMS) the freight for 10 is $644.50 by DHL Door to Door service. Bottom line price is $264.45 delivered.

Go ahead & tell me I'm a fool for considering an unknown.

 

[SamTexas]

What are the specs of the battery you intend to buy?

$644.50 for shipping: Is that by air or by boat?

 

[Dauntless]

A 36V10AH Lifepo4 battery pack is $200 & includes a 2 amp charger & BMS. (They build the BMS) the freight for 10 is $644.50 by DHL Door to Door service. Bottom line price is $264.45 delivered.

Comes with a charger? HOW NICE! But then, HOW NICE a charger?

Lithium ignorant as I am, maybe I'm just too limited to believe it would be called 36v rather than 37v or 10s. If you want to start getting nervous about the reliability of these people, start there.

Your link is NOT to a battery for sale, it's just an example of a 15C-20C 8ah battery they might build you and how it would perform.

Just one quick reference: You have no C rating, but I'll go with 10s 25C 4ah from HobbyKing, $58.33 each so 12ah would be $174.99 without the BMS. http://www.hobbyking.com/hobbyking/store/__21368__ZIPPY_Compact_4000mAh_10S_25C_Long_Lipo_Pack.html

I keep trying to soak up lithium knowledge around here so this was a great opportunity for me to notice that a little 2s charger costs less than $10, but the price seems to go up exponentially, or logarithmically if you prefer, as you add cells. This is the first time I've looked at that, I'm no expert. If you're getting a REAL 10s BMS I'll be wanting to place an order with them and get started tinkering on the cheap. Just let me know when your items arrive safely and as described. I guess it should be obvious what I'm thinking at this point. http://www.hobbyking.com/hobbyking/store/__11597__iCharger_3010B_1000W_10s_Balance_Charger.html

$644.50 for shipping: Is that by air or by boat?

Or by Tardis? I guess to deliver it before the prices went up to make the total $380 less than the shipping alone.

 

[EZgo]

What are the specs of the battery you intend to buy?

$644.50 for shipping: Is that by air or by boat?

I will have to check on your freight question but I'm almost positive this is air. It is by DHL but they use boats as well 'm sure. His first quote was $270 by sea & I picked it up in Phila.
I've been looking at & comunicating with a lot of Lithium battery sellers & this person sounds much better than 90% of them. Here is the text from his 4th email to me which includes the battery & the BMS specs.
--------------------------------------------------------------------
Dear Matt Waters

Thank you for your kindly email.

Yeah, we can make 12 cells pack, in my understanding, you want to use Lifepo4 battery(one kind materials of lithium battery), please see my explain:

For Lifepo4 cell, we will use 3.2V10AH cell, this kind cell the Max voltage is 3.65V, the Min voltage is 2.75V, so if 12 cells pack, the battery pack is 36V10AH, the battery Max voltage is 43.8V, the battery pack Min voltage is 33V,and Lifepo4 battery is better than Li(NiCoMn)O2 battery, the Lifepo4 battery pack life time is more than 2000 times, but the lifepo4 battery pack price is little higher than Li(NiCoMn)O2 battery.

Please kindly see detailed specification of Lifepo4 36V10AH battery pack
1.Lifepo4 36V10AH battery pack, the battery Max voltage is 43.8V, the battery pack Min voltage is 33V
2.With BMS,the Max discharging current is 40A, the Max instant protection current is 65-95A
3. lifepo4 3.2V10AH cell 12 cells series connection.
4.with 2A charger
5..with Alloy case(rear back type according to your email description),see picture
6.weight is about 5.4kg ,including 2A charger weight (700g).
7.price is $200/pc

We are the lithium battery manufacturer, we produce the lithium battery,our register money is $5,627,010, attached you will find our business license, you can find someone who knows chinese language to check it in china government website.

About the BMS,we produce BMS by ourself, sometimes we purchase BMS from our business partners. Following is the detailed BMS of 36V10AH
1.charging and discharging port is different, one port for charging, another port for discharing
2.Max discharging current is 40A
3.Max charging current is 40A
4.Max instant protection current is 65-95A
5.12 series
6.over current inspection delay time about 100ms
7.over charging inspection voltage 4.25V/3.9V
8.over charging release voltage is 4.1v/3.75v
9.over charging inspection delay time 1S
10.over discharging inspection delay time about 100ms
11.over discharging inspection voltage 2.8V/2.0V
12.over discharging release voltage is 3.0v/2.3v
13.inner resistance small than 20MR
14.single cell consumption is small than 10ua

Our website please visit
http://xinchibattery.zxq.net

 

[SamTexas]

For Lifepo4 cell, we will use 3.2V10AH cell, this kind cell the Max voltage is 3.65V, the Min voltage is 2.75V, so if 12 cells pack, the battery pack is 36V10AH, the battery Max voltage is 43.8V, the battery pack Min voltage is 33V,and Lifepo4 battery is better than Li(NiCoMn)O2 battery, the Lifepo4 battery pack life time is more than 2000 times, but the lifepo4 battery pack price is little higher than Li(NiCoMn)O2 battery.

Please kindly see detailed specification of Lifepo4 36V10AH battery pack
1.Lifepo4 36V10AH battery pack, the battery Max voltage is 43.8V, the battery pack Min voltage is 33V
2.With BMS,the Max discharging current is 40A, the Max instant protection current is 65-95A
3. lifepo4 3.2V10AH cell 12 cells series connection.
4.with 2A charger
5..with Alloy case(rear back type according to your email description),see picture
6.weight is about 5.4kg ,including 2A charger weight (700g).

This is the kind of specs that's intentionally ambiguous, especially coming from a battery manufacturer, who should know many times better. So ambiguous that it's almost deceptive.

a) The battery discharge rate is never mentioned! Yet a quick read could lead one to believe a continuous discharge rate of 4C.
b) The capacity of 10Ah is given without saying how it was measured. Was it at 0.1C, 0.5C, 1.0C or what? Was it discharged to 3.0V, 2.8V or 2.0V?

A legitimate battery manufacturer would have a detailed data sheet for each type of cell they manufacture. Did they send you one?

 

[EZgo]

Yes they sent me the specifications. Since it's just copied from their web site I included the link here. http://www.xcgdbattery.com/index.php?m=cp_look&typeid=&id=147

I really appreciate your questions. The more I learn about this battery technology the more confused I get. Information overload I suppose. However, because of folks like yourself I have been better able to sort the BS from the facts but I still have a way to go.

thanks

For Lifepo4 cell, we will use 3.2V10AH cell, this kind cell the Max voltage is 3.65V, the Min voltage is 2.75V, so if 12 cells pack, the battery pack is 36V10AH, the battery Max voltage is 43.8V, the battery pack Min voltage is 33V,and Lifepo4 battery is better than Li(NiCoMn)O2 battery, the Lifepo4 battery pack life time is more than 2000 times, but the lifepo4 battery pack price is little higher than Li(NiCoMn)O2 battery.

Please kindly see detailed specification of Lifepo4 36V10AH battery pack
1.Lifepo4 36V10AH battery pack, the battery Max voltage is 43.8V, the battery pack Min voltage is 33V
2.With BMS,the Max discharging current is 40A, the Max instant protection current is 65-95A
3. lifepo4 3.2V10AH cell 12 cells series connection.
4.with 2A charger
5..with Alloy case(rear back type according to your email description),see picture
6.weight is about 5.4kg ,including 2A charger weight (700g).

This is the kind of specs that's intentionally ambiguous, especially coming from a battery manufacturer, who should know many times better. So ambiguous that it's almost deceptive.

a) The battery discharge rate is never mentioned! Yet a quick read could lead one to believe a continuous discharge rate of 4C.
b) The capacity of 10Ah is given without saying how it was measured. Was it at 0.1C, 0.5C, 1.0C or what? Was it discharged to 3.0V, 2.8V or 2.0V?

A legitimate battery manufacturer would have a detailed data sheet for each type of cell they manufacture. Did they send you one?

 

[SamTexas]

I really appreciate your questions. The more I learn about this battery technology the more confused I get. Information overload I suppose. However, because of folks like yourself I have been better able to sort the BS from the facts but I still have a way to go.

You're welcome. I'm glad to see a member that can (or really tries) to see through the garbage published by these battery manufacturers. This one is bad, but nothing compared to Hobbyking RC LiCo (aka LiPo).

But there are brighter sides. A123, for example, is quite truthful with their specs. I have tested their 20Ah pouches (made in USA) and I am very impressed. So are Panasonic, Sanyo, Sony, LG, Samsung with their laptop 18650 cells.

That said, I'm still on the lookout for a reputable LiFePO4 manufacturer (since A123 is no longer around.)

 

[jpgey]

Hello, interesting paper about the saga chinese battery manufacturers:
https://docs.google.com/file/d/0B_6...ZTU5LThlYjQtYzc5YzdkZTgxMTVl/preview?hl=en_US

 

[EZgo]

Hello, interesting paper about the saga chinese battery manufacturers:
https://docs.google.com/file/d/0B_6...ZTU5LThlYjQtYzc5YzdkZTgxMTVl/preview?hl=en_US

Thank you. That was a very informative read.

 

[zeccato]

Has anybody ever heard of or used batteries from Qinhuangdao Xinchi Photoelectricity Technology Co.,Ltd.?
https://m.made-in-china.com/company-lithiumionbattery/
I'm looking at these cells with interest:
lifepo4 cells 21700 3000mah (68g.),
to make a package from 48v 27Ah, and that would be about 10 kg.
to go lighter than the bigger (26650 85g.).

Or some other brand of lifepo4 21700 minimum 3000mah?
what do you suggest?

 

[markz]

Don't bother with LiFePO4 as they are too big & too heavy compared to regular 18650's.

 

[zeccato]

Don't bother with LiFePO4 as they are too big & too heavy compared to regular 18650's.

I pedal symbolically, so (it doesn't affect) I don't have a big weight problem.