Considering Lithium

[Scott'n'Wendy]

If you don't boondock... your money will be wasted buying lithium batteries and a Li charger.

If you are always plugged in at a park, how often do you have to deal with an outage? That's the question I would consider before changing up the electrical

[Country Campers]

Scott'n'Wendy

It is not all about boondocking. With the 12 v dc fridge even traveling for a long day may cause a regular battery to not hold up.

Brian

[Scott'n'Wendy]

Scott'n'Wendy

It is not all about boondocking. With the 12 v dc fridge even traveling for a long day may cause a regular battery to not hold up.

Brian

Oh. Really? I was unaware of that. So the TV normally supplies 7 amps at 12vdc constantly. With a usual dealer battery of say 50-60ah?... That arrangement won't keep the fridge running? If that's the case I'd install a dcdc charger in the truck.... but still wouldn't add lithium if I'm always plugged in at a park.

[Jomani]

Oh. Really? I was unaware of that. So the TV normally supplies 7 amps at 12vdc constantly. With a usual dealer battery of say 50-60ah?... That arrangement won't keep the fridge running? If that's the case I'd install a dcdc charger in the truck.... but still wouldn't add lithium if I'm always plugged in at a park.

When we first picked up our 303 it had a 100 ah lead acid battery. I like to pull the trailer out onto the street to load before a trip. Even with the 165w Solar panel, the fridge would draw the battery down below 50% overnight. I wasn’t comfortable leaving food in it without running a 100’ extension cord. After I replaced it with a 200ah LiFePo4, that was never a concern. I also level the trailer on the street. With 200ah, I have never had an issue with low voltage after running slides in and out, leveling, and keeping the fridge cold. I would definitely do it again.

[acoleman43]

As another data point---we only boondock and I have 565w of solar and 560 aH of Lithium batteries. I still carry my 6300w Yamaha generator but this year we did not use it at all based on how well the solar and Lithium batteries worked. This is the first season that we used all my electrical mods that I completed through the winter. We have the 12V double door 16 cu ft fridge and it draws roughly 4A per hour or around 100 ah per day. We also now have our Starlink running on batteries and use our 2000a inverter to power all the plugs, make toast, run the hair dryer, and watch movies via DVD or streaming. Our battery bank works amazing. I do have a 125A converter/charger for the batteries and it charges them pretty quick although nearly all of our charging needs are met with the solar. Hope that helps!

We have 1260W solar array and 800 ah battery bank. We used our generator a lot this year because we were parked under trees and had overcast skies almost every day. It really depends on how much sun you get.

[bilco82]

When we first picked up our 303 it had a 100 ah lead acid battery. I like to pull the trailer out onto the street to load before a trip. Even with the 165w Solar panel, the fridge would draw the battery down below 50% overnight. I wasn’t comfortable leaving food in it without running a 100’ extension cord. After I replaced it with a 200ah LiFePo4, that was never a concern. I also level the trailer on the street. With 200ah, I have never had an issue with low voltage after running slides in and out, leveling, and keeping the fridge cold. I would definitely do it again.

This is the type of thing I"m looknig for. I'm planning 2-100 ah LiFePo4 batteries with a Powermax PM3 12V 120amp converter/charger. I'm hoping this is a good compinatoin. Any thoughts Country Campers , or anybody else? I know I'll need to use a heavier wire from the converter to the batteries. Anything else I need to add? I believe I want to connect these in parallel?

[Country Campers]

Yes connect the batteries in parallel.

In my thread I installed the new converter in the front bay near the batteries, left the stock one in position just in case and unplugged it so it was not used. Also consider adding a battery monitor, the Victron Smart Shunt is popular. I do not see a Powermax 120 amp model online, maybe I am missing it.

Brian

[COReflection]

This is the type of thing I"m looknig for. I'm planning 2-100 ah LiFePo4 batteries with a Powermax PM3 12V 120amp converter/charger. I'm hoping this is a good compinatoin. Any thoughts Country Campers , or anybody else? I know I'll need to use a heavier wire from the converter to the batteries. Anything else I need to add? I believe I want to connect these in parallel?

Here is the post thread where I showed what I installed. 303RLS Upgrade Plan - Grand Design Owners Forums (gdrvowners.com) Scroll down to #23 and you will see the write-up and pics. I relocated my converter/charger to the front compartment right near my batteries for maximum efficiency and easy of access. I then have my power for that converter remoted up front and controlled with a switch so that I can enable/disable it easily. I have the Powermax 125A converter/charger and it works great. I also use the shunt monitor. I started with (2) Lead Acid batteries in my rig with the one 165 solar panel that came with the RV but even though it would work....I needed more power and wanted more time off the grid for camping. 200ah should do the trick for what your're looking for. My 12v fridge averages about 4ah and 100ah total for the 24 hour period.

[bilco82]

Yes connect the batteries in parallel.

In my thread I installed the new converter in the front bay near the batteries, left the stock one in position just in case and unplugged it so it was not used. Also consider adding a battery monitor, the Victron Smart Shunt is popular. I do not see a Powermax 120 amp model online, maybe I am missing it.

Brian

Country Campers https://powermaxconverters.com/product/pm3-12v-series/
120 amp is the max size in the drop down Is 120 okay or is it too much? Also, I have the Furrion battery monitor from the factory, do I need to upgrade that, too?

[bilco82]

Here is the post thread where I showed what I installed. 303RLS Upgrade Plan - Grand Design Owners Forums (gdrvowners.com) Scroll down to #23 and you will see the write-up and pics. I relocated my converter/charger to the front compartment right near my batteries for maximum efficiency and easy of access. I then have my power for that converter remoted up front and controlled with a switch so that I can enable/disable it easily. I have the Powermax 125A converter/charger and it works great. I also use the shunt monitor. I started with (2) Lead Acid batteries in my rig with the one 165 solar panel that came with the RV but even though it would work....I needed more power and wanted more time off the grid for camping. 200ah should do the trick for what your're looking for. My 12v fridge averages about 4ah and 100ah total for the 24 hour period.

Thank you!! I'll check this out.

[Country Campers]

The 120 will be fine.

Yes you can use the Furrion battery monitor. howson did a Seminar on that at the Rally, maybe you attended it, if not I think it is posted in the Rally section.

Brian

[bilco82]

The 120 will be fine.

Yes you can use the Furrion battery monitor. howson did a Seminar on that at the Rally, maybe you attended it, if not I think it is posted in the Rally section.

Brian

Country Campers I did attend that seminar. howson did a very good job. I have the presentation downloaded so I can calibrate my battery monitor when I have my lithium conversion complete.
Is there an advantage or disadvantage to doing 1 200 aH battery instead of 2 100 aH batteries?

[Jomani]

Country Campers I did attend that seminar. howson did a very good job. I have the presentation downloaded so I can calibrate my battery monitor when I have my lithium conversion complete.
Is there an advantage or disadvantage to doing 1 200 aH battery instead of 2 100 aH batteries?

Depending on usage, there may be an advantage to having two 100Ah batteries over a single 200Ah. Most LiFePo4 batteries have a BMS that will limit both input and output amperage to prevent internal damage. Some batteries limit the constant output to 100 amps. If that is the case, two batteries in parallel will allow for a constant output of 200 amps. Since a 3000W inverter could draw 300 amps, multiple batteries would be a better option. If high output isn’t important, a single battery can be less expensive.

[Cate&Rob]

Just like with lead/acid batteries, there is a “redundancy” factor to having two batteries. If one fails, you still have a usable 12V supply/reserve. With one battery, if it fails, you have no backup.

Rob

[Country Campers]

I agree with Cate&Rob above. Having 2 batteries is what I would prefer.

Brian