new cells capacity expectations

[fishinjunky]

this has been going on a while - i would try to get it done ASAP -

i wouldnt even wait for the tool to check IR etc, i would want to know if they are Full Capacity as they say

that can take one day for one cell or maybe two cells a day if you do it faster


i would charge up; one cell full -- then discharge it down to 2.9V and thats it - what ever it shows as Cap out is the capacity of that cell - they may say you didnt go to 2.5V so its not accurate - but from 2.9V to 2.5v there is maybe 3Ah more so if it shows 145ah when done - i say its close enough - but only you can decided if you are Ok with 145ah cells - if they are 140ah , 135ah some of them etc, then you know its not the full 150ah - mines were all in the 185ah range - they should have been 200ah - plus is the QR codes in tact - can you scan them etc, mines were not - clear sign they were not new - take screen shots of those details for each cell you do

if you were sold a 150ah cell - and got 145ah out of it - i say its still OK - but if you got 120ah out of a 150ah - not OK you have to decided then if they cheated you - you can ask for a refund - and keep them as is - you would have to decided how much a refund you are OK with and keep them - if they agree - then thats that

if they done and keep pulling your leg after you done each cell and see the Capacity is not as advertised - then you have to decide what you want to do - if Ali express dosnt help - and the seller dosnt care - you may have a problem - you then have to start a dispute with your Credit Card or who ever you used to pay for them

i would do it as soon as you can - how long has it been since you paid - since you received them ?

it happened to me - i got a good results only after i stopped the charge with my credit card and went back and forth - till it was resolved in my favor - it could have went either way - glad it went my way - and hope my new cells are not the same story with this new seller - i have a good feeling they wont be - seller has been super nice during and after the sale so far -

we keep in contact also - when i receive them - i can test and confirm it - and i think fish will get his sooner than me - so he would know better - mines wont arrive till Feb. i hope anyway - unless there were in that boat got half of containers in the ocean

I'll be testing asap. Haven't gotten a chance to test yet but will very soon. But so far I can say the 8 x 200ah cells are in excellent condition and intact qr code. They were packaged very well. So far I'm very happy with the seller expresso recommended. She keeps in touch checking on how the cells are working for us. And always responds. I would have tested right away but I wanted to make sure I understood my new charger.

[Wavedy2]

I would have tested right away but I wanted to make sure I understood my new charger.

just a kind of trick: all the time you will spend learning the user manuelo is saving money ....


ciao !

[wheelchairer]

I have said to the seller that;
"Every cell is giving a different Ah. No 2 cells are the same so far. The highest I have received so far is 118Ah. The lowest I have achieved is a 105Ah. If these are new cells why are they not all be the same Ah?

I have spoken to experts and they say each cell should discharge 150 Ah, or at least very close to that. 145 I would have been happy with. But 105 is nowhere near 150."

In the Seller is saying;

"battery is same with description .it is really 150ah"

They are saying that only when you construct the full battery with all the cells in it will you get 150Ah. This is not true is it?

[expresso]

i dont believe that to be true


Charge each cell up full and discharge to 2.9V thats it - what ever it says is what the Capacity is -


take pictures of the results with the PL 8 -

do each cell keep track of the results - thats it

the lowest cell is most likely what the whole pack will give you - if you have 4 cells 120ah - 2 cells 110Ah - 2 Cells 105ah - in the end when you build the pack - you wont have more then 105ah - those have less in them and will reach the end first -

start a dispute ask for refund - half ? of what you paid - if that would make you happy and keep the cells - there really is no way to return them and isnt worth it if you had to pay to return - fight it - start dispute and call credit card also - if they dont want to do a partial refund at least

get your proof first - results from PL 8 -

in the future - use my seller - i think shes a winner -

and dont feel bad about it - i have many packs and up till now - only the very first packs Headways have been true and brand new cells - the rest have not been - - i wont know my new cells till i get them in March - but i feel very good about them so far - seller etc,

[Burgerman]

They are saying that only when you construct the full battery with all the cells in it will you get 150Ah. This is not true is it?

No its bollox.

the lowest cell is most likely what the whole pack will give you - if you have 4 cells 120ah - 2 cells 110Ah - 2 Cells 105ah - in the end when you build the pack - you wont have more then 105ah - those have less in them and will reach the end first -

Correct. Probably less as if they are all variable they are likely used and high impedance so you will likely get much less. They dont expect people to have the tools or knowledge to properly test. Contact your card or paypal. You should see 145Ah at least from healthy 145Ah cells.

[Wavedy2]

I have said to the seller that;
"Every cell is giving a different Ah. No 2 cells are the same so far. The highest I have received so far is 118Ah. The lowest I have achieved is a 105Ah. If these are new cells why are they not all be the same Ah?

I have spoken to experts and they say each cell should discharge 150 Ah, or at least very close to that. 145 I would have been happy with. But 105 is nowhere near 150."

In the Seller is saying;

"battery is same with description .it is really 150ah"

They are saying that only when you construct the full battery with all the cells in it will you get 150Ah. This is not true is it?

for sure you have a problemo.
here is a screen capture from my 4010 charging one of my cells pack.
capacity expected: 240A
starting voltage: 2.55V
charging time: 9 hours
end voltage: 3.60V
final capacity: 240 and a few Amps

ciao !

[Burgerman]

You cannot measure battery or cell capacity under charge accurately as you always return more than was taken out. Charging is not 100% efficient. Because of cell ineficiencies, heat from internal resistance and cable resistance losses. But as a guide it is what you would expect from a healthy cell. Even if that reading is a little higher than reaity.

You must measure under discharge. But that difference on lifepo4 is usually only around 2 to 5 % depending on cell C rate and even manufacturer. But thats around what you should expect on a healthy cell. Also its unwise to discharge life to 2.5V per cell. It increases internal self discharge level if you are doing this regularly or if unlucky. The manufacturer charges to a too high 3.65V and discharges to a too low 2.50V because they want to show the max possible capacity. But its not a healthy thing to do if you care about your cells.

[Wavedy2]

You cannot measure battery or cell capacity under charge accurately as you always return more than was taken out. Charging is not 100% efficient. Because of cell ineficiencies, heat from internal resistance and cable resistance losses. But as a guide it is what you would expect from a healthy cell. Even if that reading is a little higher than reaity.

You must measure under discharge. But that difference on lifepo4 is usually only around 2 to 5 % depending on cell C rate and even manufacturer. But thats around what you should expect on a healthy cell. Also its unwise to discharge life to 2.5V per cell. It increases internal self discharge level if you are doing this regularly or if unlucky. The manufacturer charges to a too high 3.65V and discharges to a too low 2.50V because they want to show the max possible capacity. But its not a healthy thing to do if you care about your cells.

yes you're right, but ... Not at all !

- discharging @ 2.55v even @ 2.50v (not lower), 1 time every 30/50 cycles is not bad and even good.
- you're right, amps output vs amps input are not exactely the same, but as you said, very similar, enough to have a good idea of the cell's health.
the graph is speaking by itself: my cells are 240A (mesured while discharging with an acurate amp meter) and the graph is showing a bit more.
the problem when mesuring while discharging (except if you discharge with the 4010 but I don't have time to do that usualy) is you don't mesure the self discharging and other electrical lost.
while when you mesure during charging all electron entering the cells are mesured.
for me this method is faster and very well enough acurate.
the max delta I was able to mesure is less than 2%

ciao !

[Burgerman]

- discharging @ 2.55v even @ 2.50v (not lower), 1 time every 30/50 cycles is not bad and even good.

No it is not. LiFePO4 cells hate being both fully charged, and esp if above 3.600V. And they go high impedance and worse go higher self discharge if discharged deeply.

For best service life charge at low C rate, at 3.550V CV. To around 320th to 500th of capacity.
And in service never discharge below 2.9V.

[Wavedy2]

- discharging @ 2.55v even @ 2.50v (not lower), 1 time every 30/50 cycles is not bad and even good.

No it is not. LiFePO4 cells hate being both fully charged, and esp if above 3.600V. And they go high impedance and worse go higher self discharge if discharged deeply.

For best service life charge at low C rate, at 3.550V CV. To around 320th to 500th of capacity.
And in service never discharge below 2.9V.

it is excately what i said
1 time each 30/50 cycles. not each time
afer, everyone has his own formula. and it's very interesting because that's always experience to grow

my own experience, since 10 years, show me my way is not bad and even good
i manage around 100 cells, life, 65/100 of them are 10 years old and still working like the first day

but other experiences are welcome ... and different
depending what purpose your cells are for, depending weather, altitude, temperature, even i read -but never checked that- latitude
some of my friends over 65 degrees lat north affirm their life are not responding like if they'll be in Italia


Ciao !

[Burgerman]

Your cells. Do what you wish. But I have measured the sudden increase in self discharge after testing sample cells to 2.5v. Not recommended.

[Wavedy2]

Do what you wish.

grazie mille !!!!

[expresso]

who ever just posted that -


thats not my seller -


i trust my seller and if anyone is interested - i can provide my sellers email to work out your own deal - for the first time finally i am pretty sure 99% my seller will do the right thing

[Burgerman]

Where is he shipping from?

That post is gone, another spammer.

[Arima]

who ever just posted that -


thats not my seller -


i trust my seller and if anyone is interested - i can provide my sellers email to work out your own deal - for the first time finally i am pretty sure 99% my seller will do the right thing

Yes the seller contact info would be appreciated! Does she not want to be listed here in public for some reason? I'm kinda getting excited about buying some larger cells.

[expresso]

Arima - i can PM you her email and you can take it from there


my understanding is BM dosnt allow posts from sellers to promote there cells etc,

like the person who ever posted recently - i have her contact - i can share it with anyone who wants it thru PM - fishinkill got cells from this seller - another person also is in contact with her

[expresso]

who ever just posted that -


thats not my seller -


i trust my seller and if anyone is interested - i can provide my sellers email to work out your own deal - for the first time finally i am pretty sure 99% my seller will do the right thing

Yes the seller contact info would be appreciated! Does she not want to be listed here in public for some reason? I'm kinda getting excited about buying some larger cells.

check your PM

[Burgerman]

If YOU recommend her or wish to post a link thats fine.

If someone joins, and first post is about selling anything commercial with links or emails then like the 50 or so others I delete it automtically as commercial spam links. And also ban by email, IP address, username etc. If she did this, and it was your supplier then unfortunately I didnt know that! And so she likely suffered the same fate.

If I dont do this, then we would be innundated with 1000s of spam links a day. Especially if your penis needs to be bigger, or you want new sneakers, etc.

[expresso]

she didnt do anything or post anything here

i didnt give her this site -

if you are OK with it - i can post her email - i think i even did that at first somewhere - it will get lost over time but i can post it if you want

or anyone wants just PM me - i give it to them -

[Burgerman]

Either or both!

[expresso]

annette_ou@yabohybridbattery.com

[Arima]

Sent her an email asking what size cells and the dimensions. My sunrise chair has NF22's so hopefully I can work something out. Let you know what becomes of it all. Thxs!

[expresso]

one way or another - you will find a size that fits - how large a cell is another story - hopefully at least 150ah cells or worse case 120ah cells

120ah lithium is still better than any lead - my 105ah pack is now 80ah - over 6 years time - i used it hard since its small and i go long distance -

and still at 80ah usable now - its better than brand new lead 24 size - cant beat it - best thing i done - if i have to replace it - it was worth it

i will leave it - its a 2nd back up chair - wont be used now for long distance now -

[wheelchairer]

suddenly started getting messages from that rogue supplier on WhatsApp this morning . feel bad now should I give her any money back ?

[Burgerman]

No. She/he tried to rip you off on purpose. Its their problem. Maybe if a few more did the same as you this stuff would stop. Tell them to get lost and stop begging.

[fishinjunky]

Like bm said absolutely NOT and don't feel bad they ripped you off an who knows how many others. An the excuses are bullshit they should test all cells especially if it's from a different supplier. This is what they do an are good at sweet talking an pulling sympathy because it's all about the $. Tell them to kick rocks