Lifepo4 supplier

[12kw_2021]

Purchased 32 EVE grade A cells from 18650 Battery store, arrived fast, well packed, perfect condition last July.

Have one cell acting up .......V jumps from 3.2 to 3.8 when charge current applied and BMS shuts down charge so bank cannot be charged.

Contacted them and shared BMS screenshots, and they took several days to respond, finally called and they approved an RMA, and even sent me a shipping label to return the defective cell.
Assume they will issue free replacement as they indicated a 12 month warranty.

Pretty sure this would not occur if purchased direct from China, so I am happy.

 

[KauaiMolokai]

I'm trying to figure out who I'm going to buy my lifepo4 cells from. I've been watching YouTube videos and going to forums. Jenny wu with docan or Cassie wang with qinshou. Jenny wu is $74.5 for 16x 105ah cells US warehouse. and Cassie is $54 each for 130ah shipped from china. Does anyone have any advice or experience with these two or Alibaba in general? Also open to other suppliers looking to buy this week.

Hi.
Amy Wan is a totally trustworthy honest great supplier. I recommend her 100%. Not the cheapest, just the best.

 

[upnorthandpersonal]

Any aliexpress recomendation

Don't buy cells on Aliexpress. Too many scams, no recourse what so ever, etc. Go with Alibaba instead; I won't make specific recommendations, but read the thread(s) on this forum on suppliers people have experience with.

 

[Alkaline]

Have one cell acting up .......V jumps from 3.2 to 3.8 when charge current applied and BMS shuts down charge so bank cannot be charged.

On grade A cells? Sounds like you have a bad connection to that cell and the voltage wire is getting incorrect info.

 

[12kw_2021]

On grade A cells? Sounds like you have a bad connection to that cell and the voltage wire is getting incorrect info.

Hello, Thanks for the feedback.. I will do more investigations .the JK BMS shows a resistance for the sense wire on every cell, and they are all consistent and low... but again I will loosen and tighten the sense terminal on that cell, and see if it fixes the issue., will update this post.

Ok, as long as you promise not to tell anyone, I assumed that my careful torque wrench usage at install was still correct and effective, however all 4 of the bolts on the top of the Grade A cell #14 were floppy loose. Really?

It appears that I need loctite, or need to go back and check torque on every cell again, and that should be my first check.

Sheesh.. just disabled charge on the good battery, and enabled charge on battery 2 with the misbehaving cell #14.. assume that all is well except for someone who should know better.

First feedback from vendor was check the busbars.. and I didn't bother, it took all of 20 seconds to do that.

So.. if all else fails. Stop staring at a screen, and grab a torque wrench.

Sigh

Thanks very much for the feedback/help/support.

Ps.. promise not to share my stupidity.

 

[Alkaline]

careful with the loctite if it leaks onto the terminal you will have the same situation, you need to make sure the contact between the voltage wire, buss bars e.t.c is clean.