Battery indicator readings

[Larry-NC]

Originally Posted by tomkatb

Pretty easy.

The max voltage of the battery is around 13.5.

The minimum operating voltage is near 12.

At 13.1 you are about .4/1.5 27% down or at 73% capacity

Unfortunately, no, that is not correct.

A Flooded Lead-Acid (FLA) battery's State of Charge (SOC) is pretty linear with voltage. This is not really the case with the OP's Lithium batteries. The voltage goes down very little until the SOC reaches about 20% and then it looks like a waterfall, or falling off a cliff.

This chart is for an individual cell. Four cells for a battery. Multiply the numbers on the vertical axis to see what a 12v battery looks like.



That is why knowledgeable people use a current monitor which counts amp-hours (or amp-minutes or really, electrons).

Source of this chart, and a lot of other useful information is
https://footprinthero.com/lifepo4-ba...%202.5%20volts.

[janp3rch]

Originally Posted by mbike254life

Attachment 285161Attachment 285162Attachment 285163

I currently own a 2022 Cherokee 264DBH. I am a little confused as to which indicator I should use to read my batteries current charge level. Attached are 3 pics of the various indicators 1. Is the solar charge controller located in the front storage bay 2. The dc voltage indicator near my panel 3. The battery button which lights up 4 small lights on the panel

Anyone know which one is giving my the right reading? Just upgraded to a lithium battery and I am still learning about how everything runs and operates off the battery. I understand that the voltage reading indicates how much “power” is left and I have I know that 13.1 for example is about 40% battery left (according to solar charge controller). But why are the other reading so different? 13.0 V and essentially what appears to be 4 lights indicating full charge. Thanks for any insight.

I hope you are not relying on that swaree controller to fully charge your lithium battery. Its not programmable (its set up for a lead acid battery charge mode). Your lithium requires a different charging sequence, which should have been outlined in the lithium battery documentation.


Also verify that your campers charging converter is Lithium compatible or youll only be using about 80% of that expensive battery's capabilities.


The dummy lights are just what I called them.


A lithium battery voltage is relatively constant and does not act like a wet cell battery when it comes to monitoring voltage levels. Best to use a meter that measures amperage in verses amperage out.


When I upgraded to Lithium, I kept the same converter that came with the camper, also kept the 50W solar panel on the swaree controller. But I had added a 300W solar panel and put that on a good MPPT controller with a Lithium charging profile.


The MPPT controller will insure that the Lithium battery will get topped off to the 14.6 volts that is required to keep the cells fully charged and balanced when there is adequate sun.


Took me a bit of reading when I decided to upgrade.

[mbike254life]

Originally Posted by pilotpip

A converter switches shore power from AC to DC for battery charging and other DC loads. You're confusing that with an INVERTER, which changes DC to AC for things like your fridge, and electrical outlets.



If you have an inverter, it's possible it's going to the fridge. If you don't, and want to run any of the things you mentioned you're going to need one, probably at least 2000w, and you're going to need significantly more amp hours if you want to reliably power them when there isn't much sun to recharge.

Sorry, your right I meant an inverter, I believe I must have one because some things do work while using only the battery - lights, fan, fridge, maybe because it’s from the factory its cheap and doesn’t have enough amp hours?

[bikendan]

Originally Posted by mbike254life

Sorry, your right I meant an inverter, I believe I must have one because some things do work while using only the battery - lights, fan, fridge, maybe because it’s from the factory its cheap and doesn’t have enough amp hours?

You need to understand what runs on 12v battery power and 110v AC power.
Your lights, fan and your fridge are all 12v DC battery power. (Cannon[emoji769] 12V, High Efficiency, 11 Cubic Foot Residential Refrigerator with Travel Lock)
Your trailer's webpage makes no mention of an included INverter nor an option for an INverter:
Cherokee 264DBH | Forest River RV - Manufacturer of Travel Trailers - Fifth Wheels - Tent Campers - Motorhomes https://forestriverinc.com/rvs/trave...ee/264DBH/6523

An inverter wouldn't power them. The CONverter would power them, when plugged into shore power.


Sent from my SM-G781U using Forest River Forums mobile app

[mbike254life]

Originally Posted by janp3rch

I hope you are not relying on that swaree controller to fully charge your lithium battery. Its not programmable (its set up for a lead acid battery charge mode). Your lithium requires a different charging sequence, which should have been outlined in the lithium battery documentation.


Also verify that your campers charging converter is Lithium compatible or youll only be using about 80% of that expensive battery's capabilities.


The dummy lights are just what I called them.


A lithium battery voltage is relatively constant and does not act like a wet cell battery when it comes to monitoring voltage levels. Best to use a meter that measures amperage in verses amperage out.


When I upgraded to Lithium, I kept the same converter that came with the camper, also kept the 50W solar panel on the swaree controller. But I had added a 300W solar panel and put that on a good MPPT controller with a Lithium charging profile.


The MPPT controller will insure that the Lithium battery will get topped off to the 14.6 volts that is required to keep the cells fully charged and balanced when there is adequate sun.


Took me a bit of reading when I decided to upgrade.

Thanks for the insights, the converter is compatible, mine actually has a big sticker on it that says that it is.

I know the current solar set up is doing very little. I upgraded battery because the lead acid I had, I let discharge completely and knew it was done after that.

Curious what MPPT controller and panels you went with ? Also, curious if you used the existing wiring from the factory installed solar? How difficult was it to add the solar panels to the existing panel?

[mbike254life]

Originally Posted by bikendan

You need to understand what runs on 12v battery power and 110v AC power.
Your lights, fan and your fridge are all 12v DC battery power. (Cannon[emoji769] 12V, High Efficiency, 11 Cubic Foot Residential Refrigerator with Travel Lock)

An inverter wouldn't power them. The CONverter would power them, when plugged into shore power.
Suggest that you Google "the 12 Volt Side of Life". It'll help to understand the two different RV electrical systems.

Sent from my SM-G781U using Forest River Forums mobile app

Thank you for this resource. The diagram alone helped me a ton. I had been researching and reading a lot but this really helped me understand a lot better. Appreciate it!

[jlynn721]

Originally Posted by mbike254life

Attachment 285161Attachment 285162Attachment 285163

I currently own a 2022 Cherokee 264DBH. I am a little confused as to which indicator I should use to read my batteries current charge level. Attached are 3 pics of the various indicators 1. Is the solar charge controller located in the front storage bay 2. The dc voltage indicator near my panel 3. The battery button which lights up 4 small lights on the panel

Anyone know which one is giving my the right reading? Just upgraded to a lithium battery and I am still learning about how everything runs and operates off the battery. I understand that the voltage reading indicates how much “power” is left and I have I know that 13.1 for example is about 40% battery left (according to solar charge controller). But why are the other reading so different? 13.0 V and essentially what appears to be 4 lights indicating full charge. Thanks for any insight.

The solar controller will probably give you the best info. Read the manual. It should give you amp usage and amp discharge (or a combo of the 2).

Volts doesn’t tell you much.

[clotus]

I wouldn’t use either to get a reliable reading on the battery. I know lithium doesn’t react voltage wise as much as lead acid, but to get a true SOC (state of charge) using voltage you really need to disconnect the battery, let it rest, then read the voltage.

The best way to monitor what you actually have left in the batteries is to install a battery meter utilizing a shunt. This measures actual amps coming and going and converts this to various readouts for you, most useful for me is simply percentage of battery left.

For example, you start your camping trip at 100 percent, you use some power, you make some power, and the sun goes down and solar stops adding, then you use the camper all night with various draws. You wake up in the morning and the meter will tell you what percentage you have left.

If you put a large enough solar system for your needs, you can get a full charge and cover your power needs for during the day, draw down at night, then rinse and repeat endlessly (assuming sun). OR, you use more power than you make and you can get a better idea when to turn your genny on.

Most more accurate way to monitor your battery than simply using voltage. Oh yea, most meters will give you voltage too. The Victron smart shunt meter is the easiest to install and uses your phone via Bluetooth as the display so no running wire into the rv. They also have a display kit too if you don’t want to mess with your phone. I run a Bogart Industries trimetric meter and love it, but the Victron meter wasn’t out otherwise I would probably go with them.

[kipkohl]

Clotus is exactly right, a shunt is the most accurate way to monitor your batteries and power draws. The Victron Smart Shunt is stupidly easy to install (one side hooks up to the negative postl of your battery, the other side hooks up to any wires/cables that were attached to that terminal. A small power wire hooks up to the positive post). The unit is bluetooth so you use your phone to monitor with their app. I found the app very easy to navigate, and it shows many parameters including battery charge by percentage and volts, and how long your battery will last at the current draw measured in minutes, hrs, or days.