New LiFePO4 Battery Shows 50% and Won’t Charge

[Jeff in Ferndale Wa]

I received my new Vatrer 300ah LiFePO4battery. and Vatrer 20a charger
Out of the box the battery the BMS shows 50% capacity and 13.2v
Voltmeter shows 13.0 volts at the terminals.
Since it showed 50% I decided to charge it on the workbench to 100% before installing in the trailer.
The charger will come on, charge for less than a minute then stop charging and the light turns green.
The book says if the light turns green, the battery is fully charged.
The BMS still shows 13.2v and 50% capacity.Screenshot attached
Do I have a problem?

 

[DonTom]

I received my new Vatrer 300ah LiFePO4battery. and Vatrer 20a charger
Out of the box the battery the BMS shows 50% capacity and 13.2v
Voltmeter shows 13.0 volts at the terminals.
Since it showed 50% I decided to charge it on the workbench to 100% before installing in the trailer.
The charger will come on, charge for less than a minute then stop charging and the light turns green.
The book says if the light turns green, the battery is fully charged.
The BMS still shows 13.2v and 50% capacity.Screenshot attached
Do I have a problem?

Did you check the battery voltage also with a real true voltmeter?

"Yes, the Vatrer app provides a Reset Capacity function designed to recalibrate the battery’s state of charge estimation.

• Function: This feature re-estimates the remaining capacity of the battery based on its current voltage.
• How to Access: You can find this option within the app's control buttons or by navigating to the History tab, selecting Basic Parameter, and then Initial Settings to view or adjust parameters.
• Purpose: It is used when the displayed percentage is inaccurate, allowing the system to sync its charge reading with the actual voltage state.

Note that while some third-party Android apps claim to "calibrate" phone batteries by deleting system files, the Vatrer app's reset function specifically targets the LiFePO4 battery's internal BMS estimation rather than phone hardware. "

-Don- Reno, NV

 

[Jeff in Ferndale Wa]

Voltmeter shows 13.0 volts at the terminals.

 

[Jeff in Ferndale Wa]

Did you check the battery voltage also with a real true voltmeter?

"Yes, the Vatrer app provides a Reset Capacity function designed to recalibrate the battery’s state of charge estimation.

• Function: This feature re-estimates the remaining capacity of the battery based on its current voltage.
• How to Access: You can find this option within the app's control buttons or by navigating to the History tab, selecting Basic Parameter, and then Initial Settings to view or adjust parameters.
• Purpose: It is used when the displayed percentage is inaccurate, allowing the system to sync its charge reading with the actual voltage state.

Note that while some third-party Android apps claim to "calibrate" phone batteries by deleting system files, the Vatrer app's reset function specifically targets the LiFePO4 battery's internal BMS estimation rather than phone hardware. "

-Don- Reno, NV

I cannot locate that Reset Capacity function in my app.
Considering the voltage is at 13v, from what I can find, that is probably around 50%,so that is probably right anyway.

 

[DonTom]

13v, from what I can find, that is probably around 50%,so that is probably right anyway.

They are most likely both inaccurate. It most likely gets its SOC% from its voltage so if the voltage is wrong, they are both wrong:

State of Charge (SoC)	Resting Voltage (12V)	Charging Voltage (12V)	Status
100%	13.6V	14.6V	Full / Charging
90%	13.4V	-	Good
70%	13.2V	-	Good
50%	13.0V - 13.1V	-	Nominal
30%	13.0V	-	Low
20%	12.8V	-	Low (Charge Soon)
0%	10.0V	-	Empty / Cut-off

But if your charge current is 0.0 amps while charging, it means you're fully charged and the SOC should be set to 100%.

"To access the Reset Capacity function in the Vatrer Bluetooth app, first connect your lithium battery via Bluetooth and log in. Navigate to the Control key section on the main real-time interface, where you will find the Reset capacity option. Selecting this allows the app to re-estimate the remaining capacity based on the battery's current voltage.

For additional details, you can also view battery parameters by clicking the History tab, then Basic Parameter, and Basic Settings to view nominal and cycle capacity data. "

-Don- Reno, NV

 

[DonTom]

Voltmeter shows 13.0 volts at the terminals.

I missed that message when I posted the above message

Then you really are half charged as 13.0 VDC really is 50% SOC. What is the charging voltage when you're using your 20-amp charger? It should be 14.6 VDC while charging (not green).

-Don- Reno, NV

 

[Jeff in Ferndale Wa]

I missed that message when I posted the above message

Then you really are half charged as 13.0 VDC really is 50% SOC. What is the charging voltage when you're using your 20-amp charger? It should be 14.6 VDC while charging (not green).

-Don- Reno, NV

It will only charge for 30-45 seconds then stop. The charging volts only got to 13.3-13.4

I spent the afternoon looking into this on YouTube and AI
I'm convinced I have a bad BMS in the battery.
I located the customer service number and will be calling Vatrer on Monday.
I was hoping to have the new battery installed by next Sunday when we are going to be boondocking for a week.

Thanks for the replies.

 

[DonTom]

It will only charge for 30-45 seconds then stop. The charging volts only got to 13.3-13.4

I would expect the green light on the charger to mean the voltage is at the full 14.6 VDC. Just doesn't sound like a BMS problem to me.

When you have it all charging and working as it should, please post here what the fix was.

-Don- Reno, NV

 

[Jeff in Ferndale Wa]

I would expect the green light on the charger to mean the voltage is at the full 14.6 VDC. Just doesn't sound like a BMS problem to me.

When you have it all charging and working as it should, please post here what the fix was.

-Don- Reno, NV

When the green light comes on it's only 13 volts measured at the post with a volt meter and the app says it's 13.2.
I will update when I get a solution.

 

[Mark_K5LXP]

A timed discharge test would show exactly what state of charge it is and if the BMS is active, at least for discharge.

Mark B.
Albuquerque, NM

 

[DonTom]

When the green light comes on it's only 13 volts measured at the post with a volt meter and the app says it's 13.2.
I will update when I get a solution.

Sounds like a flakey charger to me, or the incorrect model, as that could explain everything.

-Don- Reno, NV

 

[Jeff in Ferndale Wa]

Sounds like a flakey charger to me, or the incorrect model, as that could explain everything.

-Don- Reno, NV

also tried an old school charger that's been in my garage for 30+ years. Same results.Something is telling the charger that the battery is fully charged

 

[DonTom]

also tried an old school charger that's been in my garage for 30+ years. Same results.Something is telling the charger that the battery is fully charged

13.2 volts is around where a normal lead-acid charger should indicate a full charge. It should take more than a volt more to shut off (green light) a LifePO4 battery.

30 years plus? A LifePo4 battery charger?

Please post the model numbers of both chargers. I want to look them both up.

-Don- Reno, NV

 

[Jeff in Ferndale Wa]

13.2 volts is around where a normal lead-acid charger should indicate a full charge. It should take more than a volt more to shut off (green light) a LifePO4 battery.

30 years plus? A LifePo4 battery charger?

Please post the model numbers of both chargers. I want to look them both up.

-Don- Reno, NV

Here is the Vatrer charger. The old charger is NOT a LifePo4 charger.

 

[DonTom]

Here is the Vatrer charger. The old charger is NOT a LifePo4 charger.

Looks correct. But I do not understand how any battery or BMS problem can switch the charger to green below the full charge voltage of 14.6 VDC unless there is no connection at all. I would expect either a red charging or perhaps an error light (if it has such), but the green light should require the full 14.6 VDC. That is why I expect it to be a charger issue.

Your old charger acts as expected with a L/A charger trying to charge a Lifepo4.

I wonder if you have a lead/acid battery charger built into your Lifepo4 charger case. Or if it has a way to select other types of batteries. Is there a model number on it so I can look up the tech specs?

For an experiment, connect the charger to NOTHING at all from being off. Then turn it on, see if you still get red going to green in less than a minute when it is not connected to anything at all.

Then see if it acts the same as when connected to the battery.

-Don- Reno, NV

 

[John From Detroit]

I wonder if you have a lead/acid battery charger built into your Lifepo4 charger case. Or if it has a way to select other types of batteries. Is there a model number on it so I can look up the tech specs?

Many LiFePO4 chargers have "Battery detect" and will switch to LA if they think they should.

What I don't know is how to force 'em to LI

 

[Mark_K5LXP]

So is the indication the battery is at 100% charge strictly from the charger "complete" light or is there a corresponding indication from the BMS/app? Everything I'm seeing from the posts so far indicates an interruption of charge, either from a bad charger or the BMS. I don't count the 30 year old LA charger, there's no way to know what that's putting out. A totally different charge source, ideally one known to work on a different battery will help isolate the issue.

Mark B.
Albuquerque, NM

 

[Jeff in Ferndale Wa]

Looks correct. But I do not understand how any battery or BMS problem can switch the charger to green below the full charge voltage of 14.6 VDC unless there is no connection at all. I would expect either a red charging or perhaps an error light (if it has such), but the green light should require the full 14.6 VDC. That is why I expect it to be a charger issue.

Your old charger acts as expected with a L/A charger trying to charge a Lifepo4.

I wonder if you have a lead/acid battery charger built into your Lifepo4 charger case. Or if it has a way to select other types of batteries. Is there a model number on it so I can look up the tech specs?

For an experiment, connect the charger to NOTHING at all from being off. Then turn it on, see if you still get red going to green in less than a minute when it is not connected to anything at all.

Then see if it acts the same as when connected to the battery.

-Don- Reno, NV

There is no way to select a different type of battery on the charger.
I attached a pic of the model number
I started the charger while disconnected from the battery. The red light came on and the fan ran at a slow speed for well over two minutes. I reconnected with the charger still plugged in. The fan speed increased, then the green light came on after 30 seconds.

 

[Jeff in Ferndale Wa]

So is the indication the battery is at 100% charge strictly from the charger "complete" light or is there a corresponding indication from the BMS/app? Everything I'm seeing from the posts so far indicates an interruption of charge, either from a bad charger or the BMS. I don't count the 30 year old LA charger, there's no way to know what that's putting out. A totally different charge source, ideally one known to work on a different battery will help isolate the issue.

Mark B.
Albuquerque, NM

The Bluetooth app shows 13.2 v and 50% capacity.
For the brief time it will charge the voltage goes to 13.3 v and capacity does not change.

I am now thinking i should install the battery in my trailer and so how it reacts to my solar charger.

 

[Jeff in Ferndale Wa]

I put in a supporr ticket yesterday with Vartrer tech support. They responded last night with some questions. I responded, they only respond between 2100-0600 eastern time so most likely won't hear back until tomorrow.
I tried calling but got a recording that tech support is handled via email.

Now I'm thinking, like you guys, that it's a charger issue. I'll see if I know anyone with a charger. If not I may install it in my trailer and see how.it reacts to my solar charger.