Lishen 270ah-272ah cell group buy.

JJJJ

Aspiring apprentice
Joined
Feb 25, 2021
Messages
121
Looks like a fairly big range of options: 37 amps for power transmission, to 65 on another table. There is 110 if on a chassis but that would probably be pushing things. I would be dividing the power between two batteries so that would reduce the actual load.
 

stienman

Solar Addict
Joined
Jan 6, 2021
Messages
200
This would be considered chassis, however keep in mind that all these tables do is compromise between losses/heating and gauge.

A 6awg copper wire has a resistance of about 0.39 ohms per 1,000 feet.

Your bus "bars" will be about 4 inches, or 1/3 of one foot.

The expected resistance is 0.00013 ohms, or 130uOhms.

Assuming a current draw of 100A, you can expect a voltage drop of 13mV. 13mv at 100A is 1.3W of power lost to heating.

Each bus bar will give out 1.3W when you're drawing a full 100A from the battery. In an 8 cell battery that's 12w.

It's not a lot, but it does add up over time if you don't have any cooling on your batteries.

Further, unless your system is significantly undersized, chances are good you won't use the maximum current in and out constantly - you'll have peaks in that region, but generally they'll be costing you 12W of energy infrequently and for short periods of time.

Further, I suspect a lot of DIY battery connections have more resistance.

If you're drawing more current keep in mind that there is a square relationship between power and current when the resistance is fixed. You might think that 200A would result in a 24W loss, but it will actually result in 47W of power going to heat. That's significant, and could result in melting your wire insulation or even starting a fire if insufficiently cooled.

So run through the calculations yourself, decide how much heat your wires and enclosure can deal with, and plan accordingly.

Or ignore all that, use the tables, and overengineer with enough margin that you don't have to worry about it.
 

waiapasi2006

Solar Enthusiast
Joined
Mar 27, 2021
Messages
51
I can say since April, I finally received the 230Ah eve cells. The were well packed I guess... but four had some dents.
I'm sure they are good. Once the BMS comes in, I'll give it a go with a load to see how well they perform.
Thanks.
 

Johncfii

Solar Addict
Joined
Nov 24, 2020
Messages
232
Thanks! I'm in Texas so that's even better!

Trying not to steal Michael's thunder in this thread - but I haven't seen him post in this thread in awhile and I'm betting there may be lurkers that are looking for the same info so I asked.


..and I'm not sure which Amy I'm referring to - I suppose whichever one you placed your order with.

You can easily contact Amy Peng from Shenzhen Qishou Technology Limited via Ali Baba site. There is a link part way down this page:
 

JJJJ

Aspiring apprentice
Joined
Feb 25, 2021
Messages
121
Given Michael's advice, I will see if a local FedEx shipping center offers the inspect refusal route. If so, I could try to see if the destination could be diverted to that location. Given stories of deliveries without tracking activation and signature for FedEx, the above would be in an ideal world where things went right.

Michael mentioned bloating which according to Will can be a factor, especially with grade B cells. There have also been reports of scratched off QRS labels which should not be present with a new cell. Given that, if packaging is OK (mine are coming in 6 boxes instead of 4) what are recommendations? My wait is not as long as others (April), however I see that the overall cost is a third to a half of other local prebuilt options.
 

Pyrofx

Flux capacitor builder
Joined
Jul 27, 2020
Messages
525
Location
Oatman Az
Most cells will probably have scratched codes. It means no factory warranty. If it sits 6 months , is it still new ? Of course it is , just not in spec for the factory.
Now if they were crooks , and sold you 16 cells , and it tested bad........
One supplier set me 16. They tested 220 , not 280.
Found one cell that you could still read part of the code it was 220. Battled 3 weeks over it. Even after they saw the code. Told me I read it wrong.
But still waiting for refund after the admitted it.
 
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kquistorff

Solar Enthusiast
Joined
Feb 4, 2021
Messages
25
Another refund request sent to your new Email address... even though 10 days ago you told me you would send the refund the next day...
 

84bronze

Solar Enthusiast
Joined
Mar 12, 2021
Messages
30
The backlog of messages is unmanageable.

If you want to switch to different cells, or to ask for a refund, send an email to lishenrefund@hotmail.com
Hello Michael

A bit of confusion about the orders for the 272 lishen batteries. Does this mean that the order deal has fallen apart and we need to change our order or get a refund? If we are willing to wait then the order is still standing?
 
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