Do I really need a stand alone battery monitor now?

[larry2c]

I recently bought and installed two 165AH DC House LiFePO4 batteries to replace the FLA golf cart batteries that had aged out. I had an inexpensive 100A shunt and battery monitor that I put in when I installed the GC batteries and it provided me with adequate info for 5+ years. After installing the new LiFePO4 batteries the old battery monitor is not working quite right and I'm not sure exactly why. However, the DC House batteries have a built in BMS with Bluetooth and it seems to give me all the info I could ask for - SOC, discharge or charge amps as well as battery temp and individual cell info. It really doesn't seem to me that I need anything more than what that batteries are giving me and of course I have the info the solar charger provides. What are your thoughts?

 

[TacomaJoe]

The shunt should continue to provide all the information that it did in the past. Most likely issues would be not having the total Ah setting correct, and maybe not wired into the new bank correctly (missing some of the currents).

I have the Bluetooth on my 3 batteries but I like the "at a glance" display of my shunt as well. An app that I like is the LIONTRON which looks at all 3 batteries and give me the total display.

 

[larry2c]

The shunt should continue to provide all the information that it did in the past. Most likely issues would be not having the total Ah setting correct, and maybe not wired into the new bank correctly (missing some of the currents).

I have the Bluetooth on my 3 batteries but I like the "at a glance" display of my shunt as well. An app that I like is the LIONTRON which looks at all 3 batteries and give me the total display.

Maybe that's the issue - I still need to set the total AH for the new battery bank (was 110AH now 330AH). Thanks for the tip!

 

[hamrover]

Maybe that's the issue - I still need to set the total AH for the new battery bank (was 110AH now 330AH). Thanks for the tip!

I had to do this for mine as well. I noticed in a previous post that you had a picture of some Renogy brand equipment. If your shunt is like mine, even after you update the total amp hours, it will need a good full charge cycle or two before it can accurately calibrate the full condition on your shunt. After that, it should provide reliable information.

My LiFePO4 battery also has Bluetooth monitoring directly in a separate app, but what I love about the shunt is it will tell me how much longer I can continue at a given draw rate before the batteries are dead. It also tells me at a given charge rate how long it will be before the batteries are full. I don't know about yours, but my Bluetooth monitoring of the batteries internal BMS directly does not give me this information.

The additional information provided by the shunt helps me a lot when I'm planning for how long is left to top off my batteries.

 

[rich.p]

I have an interesting situation where my Bogart Trimetric monitor, which operates through a shunt, gives different readings than the Litime app that came with my battery.

Having consulted with both companies, it seems this is not anything to worry about, but it was mildly disconcerting when it first happened.

 

[ScottBrownstein]

Trimetric needs to be setup differently with LiFePO4 batteries. There is a setup procedure that you can use. Basically, LiFePO4 is more efficient with re-charge current so without the adjustment your capacity predictions will be lower than they should be when adjusted correctly.

 

[rich.p]

Trimetric needs to be setup differently with LiFePO4 batteries. There is a setup procedure that you can use. Basically, LiFePO4 is more efficient with re-charge current so without the adjustment your capacity predictions will be lower than they should be when adjusted correctly.

I should have added that I did reprogram my Trimetric to the required lithium specifications provided by Bogart and affirmed by Litime in separate communications at the time I installed the battery.

 

[Aussieguy]

I prefer the BMS as it has more information about the individual battery's overall health and performance
Shunt only is a bean counter

Use both ... if you can get the shunt calibrated for quick SOC then once a week look at the battery BMS to make sure cells are balanced etc

 

[rich.p]

One thing the app showed me that the monitor did not, was the times when the battery was balancing. Interestingly, the first week it did that daily at the end of a solar charge cycle. That seemed to have stopped as time passed.

 

[Aussieguy]

does the app allow you to make changes to the battery settings... ?
IF NO .... try the Overkill Solar APP
it's free and works on many brands of batteries that utilize the little generic (elephant icon) app

I changed "balancing when charging " to OFF
so there is more time for balancing to work.... balancing will work while charging/discarging or floating as long as the cell voltage is above the set limit

usually only see 0.004v difference in cells

Don't change other BMS settings unless you study what it can do to battery

 

[TexasJackKin]

Since I can't get my "smart" WattCycle software to work, is a smart shunt something I should look into? I have a new 280 AH "Smart" WattCycle and will have 400 watts of solar (When my TT gets here) and will be primarily a boon docker. I worry about the 12 volt refrigerator more than anything.

 

[rich.p]

Aussieguy,

If you were addressing me with that last post, the app does not allow any changes, insofar as I can tell.

I'm a pretty straightforward kind of guy without a lot of in-depth knowledge about all of this stuff. So I'm content with the thought that the battery manufacturer knows best in a case like this, and I'm not inclined to be tinkering with anything that talks to the BMS in any new way.

 

[Aussieguy]

Since I can't get my "smart" WattCycle software to work, is a smart shunt something I should look into? I have a new 280 AH "Smart" WattCycle and will have 400 watts of solar (When my TT gets here) and will be primarily a boon docker. I worry about the 12 volt refrigerator more than anything.

try the OVERKILL APP


my fridge 12v lasted 60 hours on 200ah
it cycles on/off about 50% ...

with solar you should be fine depending on your other usage
I got 740 w of panels and never turn on my converter to charge the batteries

 

[Aussieguy]

Aussieguy,

If you were addressing me with that last post, the app does not allow any changes, insofar as I can tell.

I'm a pretty straightforward kind of guy without a lot of in-depth knowledge about all of this stuff. So I'm content with the thought that the battery manufacturer knows best in a case like this, and I'm not inclined to be tinkering with anything that talks to the BMS in any new way.

try the overkill app it's free
and could come into good use one day
I have both the generic elephant that came with battery
and the Overkill APP someone here on this forum recommended
and prefer the layout and features of the overkill app

I'm too am not worried about changes except for the "balance when charging" setting

 

[rich.p]

Aussieguy, OK, I downloaded that app and will give it a spin the next time I'm over at the trailer. It will be interesting to compare its findings with those of the manufacturer's app, and my Trimetric monitor.

 

[tomkatb]

KISS

You know. Folks with major solar collectors and big batteries and inverters and miles of wires maybe. Hard core boondocking maybe.

Otherwise for most folks the battery Bluetooth monitor is plenty.

 

[TexasJackKin]

Update:

I updated my phone to the latest iOS this morning (I update it every time it tells me that there is an update) to iOS 18.3.2. Now the WattCycle app seems to be working
although, I'm a bit disappointed in the limited amount of information. It will show state of charge, rate of discharge, rate of charge, and temperature. But, nothing about time to "empty" or individual cell voltage.

But it's at least something I can work with, once I get a bit more real world experience....

 

[TexasJackKin]

try the overkill app it's free
and could come into good use one day
I have both the generic elephant that came with battery
and the Overkill APP someone here on this forum recommended
and prefer the layout and features of the overkill app

I'm too am not worried about changes except for the "balance when charging" setting

I did try the Overkill app, no joy. I did email the Overkill folks, and they got back to me in a couple of hours, saying it probably won't work on a WattCycle battery... Very friendly folks there at Overkill.....

 

[Aussieguy]

bummer :-(

 

[tomkatb]

How long to empty is a so dependent on your use I am not sure how it could be done well.

After a while your brain will do it pretty well.

We use a bit over 100 ah per day. Gas fridge and a cpap. I check every morning while boondocking.