Trouble Charging LiTime TM Batteries

[Crowz]

Show us your system and your credentials then?

I quoted the experts. You gave an opinion.

It appears Will also had to correct you. Not all controllers work the same.

I showered this morning!

Actually they do if its a single board bms (which is all you have from watching your videos). Its a glorified on/off switch when it comes to what is coming into the the cells from the main battery cables. Watch a few tear downs on the batteries like what you bought and you will see how its constructed. Will's videos are a good source.

The smaller wires you will see coming off the bms handle balancing and allow for the bms to know what the cells are at voltage wise. But when it comes to charging the battery cells themselves the current flows into the bus arrangement (large wires or actual bars) to the cells. This is raw high amp charging. The smaller leads can work at balances at very low amperage amounts. It's all it can do since those small wires would melt if each cell was being managed in the way your alluding to.

So to recap the bms in your batteries are :

Allowing it to charge or not (no changes to the amps just on or off)

Allowing it to discharge (again on or off).

Balancing individual cells at low voltage and low amperage when the battery is fully charged.

That's it. No magic past that point.

 

[sunshine_eggo]

Show us your system and your credentials then?

I think we're past that part in the other thread, no?

I quoted marketing sources the experts. You gave an opinion data supported by common knowledge and well documented BMS data.

Fixed.

It appears Will also had to correct you. Not all controllers work the same.

Will pointed out an outlier case well outside of the context of this discussion and the OP's issue/equipment.

The appropriate reaction is for you to realize that you can't count on marketing data to form a strong foundation for battery knowledge, and that you might have more to learn about LFP batteries from this forum than you can teach it.

None of us are experts at everything, but being an expert at something can trick us into thinking we have competence in other areas where we actually don't.

 

[Partimewages]

Show us your system and your credentials then?

I quoted the experts. You gave an opinion.

It appears Will also had to correct you. Not all controllers work the same.

I showered this morning!

Yep, nearly all marketing. I don't buy into that

 

[Solarcabin Channel]

I think we're past that part in the other thread, no?



Fixed.



Will pointed out an outlier case well outside of the context of this discussion and the OP's issue/equipment.

The appropriate reaction is for you to realize that you can't count on marketing data to form a strong foundation for battery knowledge, and that you might have more to learn about LFP batteries from this forum than you can teach it.

None of us are experts at everything, but being an expert at something can trick us into thinking we have competence in other areas where we actually don't.

I don't see where I claimed to be an expert?

I posted the link to support what was being discussed. I was directed to do that by the moderator.

I thought we were past that to and then this popped up.

Moving on!

 

[Solarcabin Channel]

Actually they do if its a single board bms (which is all you have from watching your videos). Its a glorified on/off switch when it comes to what is coming into the the cells from the main battery cables. Watch a few tear downs on the batteries like what you bought and you will see how its constructed. Will's videos are a good source.

The smaller wires you will see coming off the bms handle balancing and allow for the bms to know what the cells are at voltage wise. But when it comes to charging the battery cells themselves the current flows into the bus arrangement (large wires or actual bars) to the cells. This is raw high amp charging. The smaller leads can work at balances at very low amperage amounts. It's all it can do since those small wires would melt if each cell was being managed in the way your alluding to.

So to recap the bms in your batteries are :

Allowing it to charge or not (no changes to the amps just on or off)

Allowing it to discharge (again on or off).

Balancing individual cells at low voltage and low amperage when the battery is fully charged.

That's it. No magic past that point.

Ok, well when you destroy a charger or batteries because you didn't listen just don't cry to me.

Have a great day!

 

[sunshine_eggo]

Ok, well when you destroy a charger or batteries because you didn't listen just don't cry to me.

Have a great day!

You have offered no information that would prevent someone from destroying a charger.

You are responding to someone with a strong fundamental understanding of how a BMS works. You should admit to yourself that you have something to learn and then use the information provided to "overwrite" your existing erroneous understanding.

 

[Solarcabin Channel]

You have offered no information that would prevent someone from destroying a charger.

You are responding to someone with a strong fundamental understanding of how a BMS works. You should admit to yourself that you have something to learn and then use the information provided to "overwrite" your existing erroneous understanding.

Hi chip!

"but to keep my wife happy with this shit"

Probably explains it.

Moving on!

 

[dvrdwn]

I would try a different charger. There's nothing special about those batteries, very basic BMS. Sounds like the charger is being silly

I purchaced a LiTime 10 amp charger and tried it but it did not work. I returned them and repurchaced 2 other LiTime 100ah batteries w/o the low temp protection on a Black Friday sale. They charged properly. What would it take to get an external low temp sensor incorperated into the instal?

 

[Camp20144]

I purchaced a LiTime 10 amp charger and tried it but it did not work. I returned them and repurchaced 2 other LiTime 100ah batteries w/o the low temp protection on a Black Friday sale. They charged properly. What would it take to get an external low temp sensor incorperated into the instal?

I may be wrong, but doesn’t the low temp sensor just keep the battery from charging below a set temperature (32 F usually)? If these are in your fishing boat, probably not connected to solar charging, can’t you regulate this by not connecting to the charger when temperatures are forecast near 32 F. I saw some low temp BMS that don’t return to charging cycle until 60 F. Don’t recall if it was litime or ionic or Dakota. 60F looks like manually controlled charging is better anyway.

 

[VeritasCupitor]

Another Newbie here with a similar LiTime experience. I bought 4 new LiTime 12V 230Ah Plus Low-Temp Protection LiFePO4's. As received charge was 13.1V I 1st tried charging with a 20A" LiFePO4 charger from Amazon and got strange results. The battery charged for 14.2 v, 15.4 amps (never got to 20A). After over 6 hours charging, and the charger shut off with a message of "FULL" , the voltage dropped to 13.0v. Next morning its 12.89v. Emailed LiTime and got this response: "Pls do not worry. After this battery is protected from overcharge, the tested battery voltage (not the real voltage) will be lower than the real voltage. To calculate the SOC , add 0.5V to 0.7V to the tested battery voltage. The attached updated user manual screenshot is for your reference. We recommend that you take a small load and discharge it for one minute, then leave it for 30 minutes before testing the voltage, at which point the voltage should return to normal (13.33V and above)". I did what they recommended and the charge did increase.

I upgraded to a Victron Energy Smart Ip22 12vdc 30a AC charger and charged the 2nd battery - starting voltage 13.17V, bulk charging with 14.6V @ 30.0A. When it got to Absorption charging the app showed 14.6V 0.0A. When it moved into "Storage" the app showed 13.25V 0.0A. After disconnecting and resting for a day the battery was at 12.9V. I put a load of one 150W lightbulb on it for 2 minutes and now it's holding at 13.35V.

What is the normal full resting charge of a 12V LiFePO4 battery?

Thanks in advance.

 

[sunshine_eggo]

Sounds like the 12.89V is an arbitrary voltage reported by the BMS after charge protection event as evidenced by the INCREASE in voltage after you apply a load.

It may also serve as a "standby" voltage when the battery is inactive.

 

[VeritasCupitor]

LiTime claims the full resting voltage is >13.33V but other charts show 13.6V as full and 13.3V as 90%. What's a "normal" full resting charge?

 

[sunshine_eggo]

LiTime claims the full resting voltage is >13.33V but other charts show 13.6V as full and 13.3V as 90%. What's a "normal" full resting charge?

13.4-13.8 typically, but that's the sum of the cells. The BMS can report anything it wants.

 

[ryankshaw]

I returned them and repurchaced 2 other LiTime 100ah batteries w/o the low temp protection ... What would it take to get an external low temp sensor incorperated into the instal?

I'm have the same and am curious to see if anyone has any answers for you. one specific thing that I have wondered is what if I bought just 1 LiTime with low temp protection and put that in series with another liTime without it? would the low temp protection on the one protect both in series?

 

[constantspeed]

Another Newbie here with a similar LiTime experience. I bought 4 new LiTime 12V 230Ah Plus Low-Temp Protection LiFePO4's. As received charge was 13.1V I 1st tried charging with a 20A" LiFePO4 charger from Amazon and got strange results. The battery charged for 14.2 v, 15.4 amps (never got to 20A). After over 6 hours charging, and the charger shut off with a message of "FULL" , the voltage dropped to 13.0v. Next morning its 12.89v. Emailed LiTime and got this response: "Pls do not worry. After this battery is protected from overcharge, the tested battery voltage (not the real voltage) will be lower than the real voltage. To calculate the SOC , add 0.5V to 0.7V to the tested battery voltage. The attached updated user manual screenshot is for your reference. We recommend that you take a small load and discharge it for one minute, then leave it for 30 minutes before testing the voltage, at which point the voltage should return to normal (13.33V and above)". I did what they recommended and the charge did increase.

I upgraded to a Victron Energy Smart Ip22 12vdc 30a AC charger and charged the 2nd battery - starting voltage 13.17V, bulk charging with 14.6V @ 30.0A. When it got to Absorption charging the app showed 14.6V 0.0A. When it moved into "Storage" the app showed 13.25V 0.0A. After disconnecting and resting for a day the battery was at 12.9V. I put a load of one 150W lightbulb on it for 2 minutes and now it's holding at 13.35V.

What is the normal full resting charge of a 12V LiFePO4 battery?

Thanks in advance.

I bought three new Li Time 230Ah Plus with LTCP and am having exactly the same experience as you describe. All of them arrive with a voltage around 13.11v. I charge with a Victron IP22 30A charger, and when it completes the cycle, the battery reads 12.89v or 12.96v ----this has been the case with all three of these batteries. I connected each to an inverter and run a space heater for a few minutes, and the voltages of each battery, after resting, does tick up to 13.33v or close to it. The outstanding question remains, however, if any of the batteries attained a full charge?
Somehow I am sure the BMS they are using is the culprit here. Is it a problem or a feature? Not sure. Will need to try a capacity test discharge, but am not really happy that I am going through all of this run-around with these batteries. I have several other smaller (100Ah) Li Time and Ampere Time batteries that I have been quite happy with, and without issues like this. The 200A BMS in these units must be programed differently.

Will does recommend this specific model---the Li Time 230Ah with LTCP, on his website---but I have yet to see a video from him specifically talk about this battery, let alone test it and tare it down. Would really be interested if he encounters the same initial experience.

 

[sunshine_eggo]

I bought three new Li Time 230Ah Plus with LTCP and am having exactly the same experience as you describe. All of them arrive with a voltage around 13.11v. I charge with a Victron IP22 30A charger, and when it completes the cycle, the battery reads 12.89v or 12.96v ----this has been the case with all three of these batteries. I connected each to an inverter and run a space heater for a few minutes, and the voltages of each battery, after resting, does tick up to 13.33v or close to it. The outstanding question remains, however, if any of the batteries attained a full charge?
Somehow I am sure the BMS they are using is the culprit here. Is it a problem or a feature? Not sure. Will need to try a capacity test discharge, but am not really happy that I am going through all of this run-around with these batteries. I have several other smaller (100Ah) Li Time and Ampere Time batteries that I have been quite happy with, and without issues like this. The 200A BMS in these units must be programed differently.

Will does recommend this specific model---the Li Time 230Ah with LTCP, on his website---but I have yet to see a video from him specifically talk about this battery, let alone test it and tare it down. Would really be interested if he encounters the same initial experience.

Did you observe it hit ~14.4V while passing current? If so, then they hit full or "dang near full."

Have you tried charing to 13.8V with a 2 hour fixed absorption period?

 

[constantspeed]

Did you observe it hit ~14.4V while passing current? If so, then they hit full or "dang near full."

Have you tried charing to 13.8V with a 2 hour fixed absorption period?

These batteries seem to do better with their respective BMS, if the charger max voltage is set below 14.6v. I have been experimenting with the Victron Ip22 30A charger, and the batteries seem happiest if the max charge voltage is 14.4v (manual says 14.4v +/- .2v). When left to do it's thing, it completes the task, but the battery ends up at 12.92v, until a load is again placed on the battery, after which, it recovers to 13.21v, but I would like to see it recover to 13.3 or more as a resting voltage. Next step is to setup a capacity test, to see if full capacity is there.

 

[sunshine_eggo]

These batteries seem to do better with their respective BMS, if the charger max voltage is set below 14.6v.

ALL batteries do.

I have been experimenting with the Victron Ip22 30A charger, and the batteries seem happiest if the max charge voltage is 14.4v (manual says 14.4v +/- .2v). When left to do it's thing, it completes the task,

Have you watched it at completion? I think this is the key. If you SEE it hit absorption AND flow current, it's full. If not, you're likely seeing premature charge termination due to BMS HVD.

but the battery ends up at 12.92v,

I'm convinced it's a post-charge protection event and/or a standby voltage if the battery is dormant for X seconds/minutes/hours.

until a load is again placed on the battery, after which, it recovers to 13.21v, but I would like to see it recover to 13.3 or more as a resting voltage. Next step is to setup a capacity test, to see if full capacity is there.

Agreed. 13.3V would be more reassuring. 13.4V moreso.

Have you tried charing to 13.8V with a 2 hour fixed absorption period?

 

[VeritasCupitor]

If I were to Disconnect the charger at the end of the Absorption charge period when it at 14.6V, would the resting charge stay higher? I'm not sure if the charger app is showing the battery voltage or the charger voltage.

During the Bulk charge, while charging was set for 14.4V the app showed a voltage of 13.54V. I assumed this was the battery voltage:

 

[VeritasCupitor]

I have several other smaller (100Ah) Li Time and Ampere Time batteries that I have been quite happy with, and without issues like this.

What do the (100Ah) Li Time batteries charge to for their resting voltage?

 

[sunshine_eggo]

If I were to Disconnect the charger at the end of the Absorption charge period when it at 14.6V, would the resting charge stay higher?

Unknown. You'd have to see for yourself. If it high high voltage protection as evidenced by jumping to 14.6V with an immediate drop to 0A (no taper), then I would expect it to read ~12.9V immediately after charging.

I'm not sure if the charger app is showing the battery voltage or the charger voltage.
View attachment 178775

Charger voltage. With no current flowing, it's reporting its set absorption voltage.

During the Bulk charge, while charging was set for 14.4V the app showed a voltage of 13.54V. I assumed this was the battery voltage:
View attachment 178776

It's whatever voltage it was seeing in response to the 30A current. Battery voltage at the battery terminals would be a little lower than 13.54V.

 

[constantspeed]

I'm convinced it's a post-charge protection event and/or a standby voltage if the battery is dormant for X seconds/minutes/hours.

Agreed. I think it is a post-charge event.

Have you watched it at completion? I think this is the key. If you SEE it hit absorption AND flow current, it's full. If not, you're likely seeing premature charge termination due to BMS HVD.

The History tab in the Victron app will show the charge progress, and if it was "Completed" or stopped by other means. And yes, this followed through to completion for full cycle.

Have you tried charing to 13.8V with a 2 hour fixed absorption period?

I have not. That might be a next step to investigate. First will try a capacity test.

 

[constantspeed]

What do the (100Ah) Li Time batteries charge to for their resting voltage?

I have the Li Time 100Ah Mini, and it has been sitting waiting for a project for a number of weeks now after fully charging, and is resting at 13.37v. The other Ampere Time (previous name of company) 100Ah batteries are currently part of a 500Ah battery bank in our RV trailer. I cannot tell you exactly what they are resting at right now, but typically are above 13.3v for the entire bank.

 

[jspann]

I would try a different charger. There's nothing special about those batteries, very basic BMS. Sounds like the charger is being silly

The mini has a "new improved" bms devloped by litime. Has anyone done a deep dive analysis of this bms? I had to set charge down to 14.0v or absorption went eratic both voltage and current with usual setting.
The mini has a resting 100% voltage of 13.33. This is lower than I expected yet litime recomended charge settings are still the same as prismatic.
Under load my mini was pulling 160A without cutting off. Bms should have cut out.

 

[Robar]

Just found this thread recently since I've had the same issue with my new Litime 12V 230Ah Plus battery. So far I've only tried charging it with their 20A charger and seen the same over-voltage protection kick in (though I wasn't monitoring the voltage closely, so I don't know what it got to). Loading for a few minutes brought the resting voltage back to about 13.3V. I contacted Litime support to see if I could get more information on their BMS, specifcally around the cell balancing function, and also to get their recommended settings for charging (sent a list of relevant settings for Victron MPPT and AC charger that I'm planning to use), and they wrote back with the following that I wanted to pass along to anyone else with one of these:

This is our new battery protection function, [Full Charge Protection Function].
This function provides more comprehensive protection for the battery and better performance of the battery system in two ways.

① Reduces voltage oscillations in the battery or system, maintains system performance and prevents abnormal system shutdown.
In situations where the battery needs to be connected to the charger for a long period of time, repeatedly turning on the battery after it has been fully charged can cause voltage oscillations in the battery or system (the battery voltage repeatedly cycles from resting down to charging up), which can affect system performance and even cause the system to shut down abnormally.

② Extend the life of the battery.
When a LiFePO4 battery is kept on high voltage charge for a long period (14.6V full charge voltage), its life span decreases relatively faster.
This function allows the battery to turn on the charge protection after a full charge, and then turn on the charge again after a certain discharge or resting voltage below a certain value, which can effectively circumvent the problems that may arise when the battery needs to be connected to the charger for a long time to charge without discharging.

After this battery is protected from overcharging,
the tested battery voltage (not the real voltage) will be lower than the real voltage.
To calculate the SOC (%), add 0.5V to 0.7V to the tested battery voltage.

We recommend that you take a small load (50W or above)and discharge it for 3-5 minute,
then leave it for 30 minutes before testing the voltage,
at which point the voltage should return to normal fully charged voltage(13.33V and above)


Here is some info about the BMS of the 12V 230Ah Plus battery for you：
Balance voltage for single cell：3.525±0.025V
Balance current for single cell：35±10mA
The balance module is working, it is recommended to charge with a small current, and the balancing time will be longer and more conducive to balancing.

Here are the recommended setting parameters for you：
Absorption Voltage：14.4V~14.6V
Float Voltage: 13.8V
Re-Bulk Voltage Offset: 13.0V
Tail Current：4.6A
Storage Voltage：50% SOC (see attached SOC form)
Bulk Time Limit： default
Re-bulk Current：default
Absorption Duration (Adaptive/Fixed)： Adaptive
Maximum Absorption Time (for Adaptive)/Absorption Time (for Fixed)：2h0m
Repeated Absorption：default
Others are default.

This pretty much confirms what others have been speculating, and does seem to offer a way to let the BMS balance the cells, which is good. It also seems that this is a new feature that has been added recently, so that's why we haven't been seeing this with previous batteries.

Anyway, I'm still looking into all of this and trying to make sense of the various threads and recommendations for LiFePO4 charging and also BMS cell balancing, so I'd appreciate anyone's thoughts on the Litime recommendations. So if I want to try to balance the cells, can I do so with a regular bench-top power supply set at 14.1V (3.525 * 4), and just use the current limiting to set it at 35mA?

Thanks for all the info so far, and I hope these additional recommendations might be helpful to others.