First test results Winston vs LiTime

[sailorboy1]

so back to to the test

There has been differences between the banks. But has any been practical user differences that would matter in operation?

[s/v Jedi]

Originally Posted by sailorboy1

so back to to the test

There has been differences between the banks. But has any been practical user differences that would matter in operation?

No, the batteries creep apart during charge and discharge but only a certain amount and then they balance again when nearing low or high soc%.

Basically exactly like I expected, but I did find the difference was more than I expected. I then thought that it must be the MOSFET based BMS that adds resistance but someone also mentioned that the cells themselves have a different internal resistance curve.

All that matters is that every full charge all the batteries are full as they balance out in the process. This makes it very easy to just plug in batteries like power modules. You can even plug them into separate locations to boost power on the other side of a long cable run etc. and it will all simply work.

[wholybee]

Originally Posted by Chotu

Been stoping my Li Time bank at 3.55 for 13 months now, cycling up/down about 25% of capacity daily. Now with higher requirements while the heaters fight the refrigerator and freezer, cycling down 33% a day and charging every 3 days from nearly empty to BMS overcharge cutoff at 3.65. The higher stop is due to a different non-adjustable charger when charging through the generator.

Am I all good for balancing purposes?

You are good for balancing purposes. You are likely overcharging the batteries slightly unless you are able to achieve a high C rate. Whether this will dramatically reduce the life, or only slightly reduce the life, I don't know.

How many amps is the charger you are using? Do you have a Victron or similar meter that you can set to alarm at 14.2V so you can manually stop it? Or you can use a Victron battery protect, and set that to a lower voltage.

[s/v Jedi]

I don’t like charging into HVC on purpose. HVC is a last effort to save your battery from ruining it and it should never happen.

But hey you can always buy new ones

[senormechanico]

Originally Posted by sailorboy1

so back to to the test

There has been differences between the banks. But has any been practical user differences that would matter in operation?

You said you would unsubscribe.... See #47

[sailorboy1]

Originally Posted by senormechanico

You said you would unsubscribe.... See #47

nothing better to do I take it

[CaptainRivet]

Originally Posted by s/v Jedi

I don’t like charging into HVC on purpose. HVC is a last effort to save your battery from ruining it and it should never happen.

But hey you can always buy new ones

well the manual states you should charge to 3,65V and the small passive balancer in them needs this time to balance them. to pamper them with 3,55V or even less is contraproductive, especially when loading or cycling hard is exactly wrong with these surprise boxes without any external communication.

And because its a closed surprise box without any external communication there are only 2 ways to find out if the battery works as expected or not
1) charge to HVC at 14,4V and see if it stop at 14,4V, if below you already have a runner and battery is unbalanced, the more you are away from 14.4V the worse it is already. the earlier you see they have a runner, the more chances you have to get them back to balance without cutting them open.
2) do a full capacity test, means charge till HVC and discharge till LCV and see how much capacity they have, do it after a month again and see the difference. total is good but delta is more important so a smartshunt comparison is enough.
that is what you should track.
just looking at what AH goes in and out and how they differ from the winston tells you just they are working but not how good.
that they share the load was clear...if you look at the Frankenstein battry from Andy's offgrid garage you can see that even diffent capacities and manufacturer still work quite well and whats in the LI-Time is definitly better then this Frankenstein one...
that really opened my eyes that even chunk put togehter with a good active balancer works quite well...there are even bloated Hisense cells in it.

[s/v Jedi]

Originally Posted by CaptainRivet

well the manual states you should charge to 3,65V and the small passive balancer in them needs this time to balance them. to pamper them with 3,55V or even less is contraproductive, especially when loading or cycling hard is exactly wrong with these surprise boxes without any external communication.

And because its a closed surprise box without any external communication there are only 2 ways to find out if the battery works as expected or not
1) charge to HVC at 14,4V and see if it stop at 14,4V, if below you already have a runner and battery is unbalanced, the more you are away from 14.4V the worse it is already. the earlier you see they have a runner, the more chances you have to get them back to balance without cutting them open.
2) do a full capacity test, means charge till HVC and discharge till LCV and see how much capacity they have, do it after a month again and see the difference. total is good but delta is more important so a smartshunt comparison is enough.
that is what you should track.
just looking at what AH goes in and out and how they differ from the winston tells you just they are working but not how good.
that they share the load was clear...if you look at the Frankenstein battry from Andy's offgrid garage you can see that even diffent capacities and manufacturer still work quite well and whats in the LI-Time is definitly better then this Frankenstein one...
that really opened my eyes that even chunk put togehter with a good active balancer works quite well...there are even bloated Hisense cells in it.

My manual doesn’t say that.

[CaptainRivet]

Originally Posted by s/v Jedi

My manual doesn’t say that.

https://www.litime.com/blogs/blogs/b...ithium-battery


reference charge voltage 14,4 or 28.8 so 3,6V, acceptable 14.2 till 14.6V so 3,55 till 3,65V per cell so rather on the high side which makes sense due to passive balancer.
all their equipment charge till 14,6V (AC and DC2DC chargers)
by the way cells and BMS are Gangfeng

[s/v Jedi]

Originally Posted by CaptainRivet

https://www.litime.com/blogs/blogs/b...ithium-battery


reference charge voltage 14,4 or 28.8 so 3,6V, acceptable 14.2 till 14.6V so 3,55 till 3,65V per cell so rather on the high side which makes sense due to passive balancer.

by the way cells and BMS are Gangfeng and not EVE.

So it didn’t say 3.65V, right? See how you pull everything to the extreme? You state 3.65 which is the absolute maximum but 3.55 is good too.

These instructions are general ones and while they have access to factory new cells and most probably match them, many of their products do have cells in parallel and therefore are prone to imbalance.

My particular batteries only have cells in series so are much less prone to imbalance and I will charge them higher than what I do by default, which is 3.45V instead of 3.55V when I notice irregularities.

I believe they use a BMS with passive balancer so I guess it will start shunting cells on a per cell voltage basis, which means it can already partially balance below 3.55V when there is a high cell.

[CaptainRivet]

Originally Posted by s/v Jedi

I don’t like charging into HVC on purpose. HVC is a last effort to save your battery from ruining it and it should never happen.

But hey you can always buy new ones

its not HVC, its end of charge voltage by internal Mosfet BMS 14,6V...
HVC is 3,75V

[CaptainRivet]

Originally Posted by s/v Jedi

So it didn’t say 3.65V, right? See how you pull everything to the extreme? You state 3.65 which is the absolute maximum but 3.55 is good too.

These instructions are general ones and while they have access to factory new cells and most probably match them, many of their products do have cells in parallel and therefore are prone to imbalance.

My particular batteries only have cells in series so are much less prone to imbalance and I will charge them higher than what I do by default, which is 3.45V instead of 3.55V when I notice irregularities.

I believe they use a BMS with passive balancer so I guess it will start shunting cells on a per cell voltage basis, which means it can already partially balance below 3.55V when there is a high cell.

all there own charging equipment is 14,6V, so 3,65V is what they do.

not extreme. and the BMS starts balancing normally above 3,45V in these BMS with as much as 25 to 100mA if your lucky which is not much...so you need to give them all the time they can get.

you can simply only see that you have a runner when BMS switches off when EOF is reached on total voltage, thats the only real indicator you have on this ones. you don't have cell volatges at all so you cannot see anything at 28.2V or 28.4V.....only when they switch off and that means a runner hit 3,65V and if lucky with 3,55V others are at 3,45V, thats already an imbalnce of 1AH on a 200AH bat and with 25 to 100mA takes ages to balance. calendar aging will come earlier and 3,65V is not extreme.

[s/v Jedi]

Originally Posted by CaptainRivet

its not HVC, its end of charge voltage by internal Mosfet BMS 14,6V...
HVC is 3,75V

There you go again, completely senseless, incoherent and incorrect. We’re done.

[CaptainRivet]

Originally Posted by s/v Jedi

There you go again, completely senseless, incoherent and incorrect. We’re done.

nothing incoherent and incorrect. typical values in these drop in mosfet BMS are 2,5V LCV and 3,65V EOC and HVC 3,75V.
charging to 14,6V and it shuts off at 14,4V you already know you have a runner and keep it like that if its stays at 14,4V you know its natural imbalance of the different cells used and balancer can cope. if it goes down to 14,3V you know you have a problem that balancer cannot cope and need more time in the higher area.
no chance seeing that when charging to 3,45 or 3,55V.

[s/v Jedi]

Yesterday I moved the battery monitor displays to my new panel and after figuring out which is which etc. I decided to do a full charge to synchronize. And look now, next morning… still in sync!