Question LiFePo4 Charging

[Texas Clodhopper]

I have 4 - 230 AH LiFePo4 batteries.
Victron Energy Smartshunt 500amp
LI-Bim
Magnum ME-ARC 50 Remote

Questions:
1. When on shore power, my batteries only charge to 85% SOC. If I turn the master battery switch off and back on they will charge to 100% and then go to float.

2. I started driving yesterday with the batteries 56% SOC, 13.09V. After driving 7 hours, the batteries were at 68% SOC, 13.33V. They charged only to 85% overnight and stopped charging on the Magnum display.

Whats going on? I think I must have a setting on the ME-ARC wrong. What say y'all?

 

[Richpatty]

I would look at the magnum…

Here are the settings I use for my Lithoium, but each manufacturer may be slightly different.

To set for lithium battery charging in a 12VDC system:

• Press the SETUP button;
• Turn SELECT knob to 03 Charger Setup, Press the Select knob;
• Rotate to 03C Battery Type, press Select knob;
• Rotate to Custom, press Select knob;
  • Absorb volts = 14.4VDC;
  • Float volts = 13.2VDC;
  • EQ volts = 14.4VDC;
  • EQ Done Time = 0.1hrs
• Rotate to 03D Absorb Done Time, press select knob;
• BattleBorn wants this set for 0.5hrs per parallel battery string, if you have 8 12v batteries then this would be 4hrs.
• Rotate to 03G, press Select knob;
• Rotate to Silent, press Select knob;
• ReBulk volts = 13.2VDC

I will say I also have times ,when I don’t get back to 100% SOC when charging off the magnum, but usually get over 90%. My solar (Victron controller) always gets it back to 100%, so I have not thought about it too much.

 

[Texas Clodhopper]

Thanks Rich.

 

[Texas Clodhopper]

@Richpatty, I had a couple of settings that were different than yours. After I had installed the new remote, I called Solar Energy, and they walked me through the setup.

 

[Richpatty]

Cool. What did they have you change?

 

[Texas Clodhopper]

I changed to your settings from what they had instructed last week. Their EQ done time was 4 hours, and the rebulk volts were 12.8. I changed it to 13.2 done time of 0.1, it immediately started bulk charging.

We are on shore power but will be doing some overnight boondocking beginning Friday and I will get a better idea if this fixed my issue.

Thanks again for you help and I'll let you know how it works out.

 

[Neal]

Do your batteries have anything to tell you such as via bluetooth what the BMS thinks the state of charge is?

Does your shunt need to be calibrated?

It's odd that you have a mix and match, i.e. how does your ME-ARC50 know the SOC? Does it work with the Victron shunt? All I know of is the ME-BMK that works with the Magnum inverter for SOC. I'm guessing you have the no shunt version? It may need to be recalibrated, I had to do that a time or two. I think disconnecting power to it and then reconnecting will put it back into sync mode.

 

[Texas Clodhopper]

The battery's BMS agrees with my Victron Smart Shunt, and my Smart Shunt agrees with the ME-ARC 50L.

 

[Neal]

With my install, I was told to discharge them monthly. It helps keep cells balanced, etc. I'm in the middle of my monthly discharge now, takes about 4 days. Consider discharging yours to 20% and then let them charge up from there and see how it goes.

 

[AbdRahim]

I talked to them (SES) about running them down and they told me that would just wear them out prematurely.

 

[Neal]

I talked to them (SES) about running them down and they told me that would just wear them out prematurely.

I emailed SES and leadership there and it appears I was given conflicting guidance. Here is their response to help clear this up, at least for now. The only thing is different people seem to have different opinions on this so one tech may say this, another tech may advise what I was originally told. I think I'll just put 90 psi in all of my batteries and that should clear things up!

To clear up any misunderstanding, here is the actual tip I give to all my customers in regards to Lithium Batteries.

Yes, it is better to leave your batteries at 100%, to prevent wear and tear.

(If put into storage, ensure that everything is turned off, and leave the batteries around 90% to allow the batteries to be stored at a comfortable charge level).

In your case, I noticed that you have the Victron Smart Lithium Batteries, which I can see where the “cycle” advice came from.

You do not have to discharge the batteries that much, rather, down to around 80% and back up is good enough.

The reason for this advice is because the Victron Smart Lithium Batteries can go into a “Unknown” state if the battery is left alone for too long (around 1 month).

This can cause issues for the Victron System sometimes, but the remedy to this issue is:

1. If left alone for a month or two, you can simply apply charge and bring them out of the “Unknown” state.
2. If left alone for longer, at a low charge (less than 30%), and poor environment (freezing), you will have to remove the batteries, and apply a charge with something similar to a car charger in a “not-freezing” environment

To prevent the worst-case scenario from happening, we tell customers to “cycle” the battery once a month.

However, you do not need to cycle it all the way down.

Just 10%-20% will do.

and a follow up said:

Remember, this procedure is tailored towards the Victron Smart Lithium Batteries.

I have not come upon any other brands that would do this as a procedure to ensure better protection for the batteries.

Always good to see that Victron is trying their best to ensure things works and prevents us from damaging our investments.

 

[Texas Clodhopper]

All I can comment on and strongly recommend is changing the winter air in your tires to the summer blend. It will make a 3-5 mpg improvement on your mileage. I did mine right before leaving TX and I the mileage improvement is so good that I don't care what I pay for fuel.

 

[AbdRahim]

All I can comment on and strongly recommend is changing the winter air in your tires to the summer blend. It will make a 3-5 mpg improvement on your mileage. I did mine right before leaving TX and I the mileage improvement is so good that I don't care what I pay for fuel.

You pay for fuel? I thought those were all air-ride.

 

[MemoriesByTheMile]

All I can comment on and strongly recommend is changing the winter air in your tires to the summer blend. It will make a 3-5 mpg improvement on your mileage. I did mine right before leaving TX and I the mileage improvement is so good that I don't care what I pay for fuel.

I would highly recommend not only swapping out the winter air for summer air in the tires - but also consider fully draining your batteries of the sluggish winter electrons and recharging with the highly active summer electrons.
Puts a little extra oomph in your step!

 

[Kevind]

Victron Smart Lithium batteries sound like they have a bug in their BMS that gets in a weird state that recharging the batteries will cause to reset.

I have my batteries on the converter / charger whenever the power company can keep power to the pedestal. Which the past winter was most of the time. My batteries performed well the 3 times we lost pedestal power for up to 3 days. We had a fairly cold winter, never less than 8 degrees F but less than 32F for a few weeks. I don’t have battery heaters, so they probably weren’t charged every day.