When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
Why did you consider the 300 ah battery to be a little small?
just curious how you are using them such that they are potentially a limiting factor.
My previous toy hauler had 4 golf cart batteries in it, which were huge & heavy. The current trailer came with a pair of group 27, or 29s if I recall. The lithium battery is noticably smaller & lighter than what I had before. It's mostly a mental thing I suspect. Combined with seeing some of the monster installs out there. 300ah has been fine for our daily needs so far & gets generally charged up daily by the solar every day if there is reasonable sun. We have a Starlink dish which could use 120 ah on its own if we left it on all the time, which would be pushing half the battery all on its own. We have a propane fridge (one of the last ones apparently, all the new ones are 12v electric compressors), which probably saves us around 100ah.
Only a few trips last year after putting in the 300ah lithium & we haven't ran out of juice yet. But I do manage power usage pretty aggressively. We probably would be out of juice or really low in the morning if I forgot the Starlink on overnight & it was cold enough to run the furnace a fair bit. A bit more buffer would be nice, but I can't justify it.
In 3 days will be our 9th year of 500ah lfp fulltime use. 3,100 (boondocked) of 3,284 days. Amazing the power these batteries have at all levels of SOC and pulling large loads with solar doing it's thing quietly in the background.
In 3 days will be our 9th year of 500ah lfp fulltime use. 3,100 (boondocked) of 3,284 days. Amazing the power these batteries have at all levels of SOC and pulling large loads with solar doing it's thing quietly in the background.
Hope you experience is a good as ours has been.
Thank you sir! We are excited about it and grateful we didn't jump into the LFP game 7+ years ago when we were contemplating it. I am now gathering up the settings for the Victron MPPT and BMV-712 so that when the converter charger is selected and purchased we will be ready to install the LFP battery.
Yes, congrats Sous. You'll love those things. We are on our 3rd year with ours. We have (2) 280ah. They work awesome and it's nice to give the genny a rest.....
Going to LiFePo batteries is a game changer, I've fitted a Fogstar Drift-Pro 560ah in the space that used to hold 4 70ah leisure batteries, giving me nearly 4 times the usable power, I started with a Fogstar 50a shore power charger augmented with a Victron Orion XS DC-DC 50a, upgraded alternator to MechMan 400a, thinking that I can add another XS later (although I've heard Victron are bringing out a 100a DC-DC soon....)
But I now have the rest of the system, solar, inverter etc & boy does it perform!
We should be able to go off-grid indefinitely now & run the AC when necessary, under testing i was able to use the AC without drawing from the battery.
I started with 600aH [2 DIY 304aH batteries] and the following year, I made space for two more. With a total of over 1200aH, I'm doing well.
I did swap out the converter to a 125A, mostly so I can charge the batteries faster when I do plug in. The stock electrical distribution panel will accept a 20A load for the converter. I did need to swap out the 15A breaker. I plug into my shop with a 20A cord and electrical receptacle.
My next project is to figure out how to get the alternator to charge the batteries while on the go. I do have plans and space for a 2nd alternator to help with that too.
@Sous Sorry brother just got my inbox cleared. like I said the inverter I have is the same unit as you have and you can have it for postage as a spare as it just taking up space in my shop. I also have a xantrex charger of the same rough year that can charge lithium as well. once again free to a good home minus postage. you will love the versatility of the LiFePo4 batteries. but as I said before make sure the BMS in the bat allows for top balancing in some fashion. if it does not you can crack the case and manually top balance from time to time. it is common in the cheap LFP battery world
@Sous Sorry brother just got my inbox cleared. like I said the inverter I have is the same unit as you have and you can have it for postage as a spare as it just taking up space in my shop. I also have a xantrex charger of the same rough year that can charge lithium as well. once again free to a good home minus postage. you will love the versatility of the LiFePo4 batteries. but as I said before make sure the BMS in the bat allows for top balancing in some fashion. if it does not you can crack the case and manually top balance from time to time. it is common in the cheap LFP battery world
I started with 600aH [2 DIY 304aH batteries] and the following year, I made space for two more. With a total of over 1200aH, I'm doing well.
I did swap out the converter to a 125A, mostly so I can charge the batteries faster when I do plug in. The stock electrical distribution panel will accept a 20A load for the converter. I did need to swap out the 15A breaker. I plug into my shop with a 20A cord and electrical receptacle.
My next project is to figure out how to get the alternator to charge the batteries while on the go. I do have plans and space for a 2nd alternator to help with that too.
Alternator from the truck or RV? The 7 pin for standard travel trailers is usually fused to 30@. However there is generally about 20' of wire between the front of the truck & the socket with no telling how much wire behind the plug to the batteries in the trailer. At best, you are looking at 8 gauge wire. The voltage drop for 20' of 8 gauge wire over 20' is going to be about 1 volt. Dropping from 13v at the alternator to 12v at the battery means you wouldn't be charging a battery much at all.
You'll need to run some beefy wire to a dedicated plug on the back of your tow rig to avoid voltage drop. Even then you'd probably be looking at a DC to DC power converter to get decent charging voltages.
It's amazing how problematic voltage drop can be on low voltage electrical systems. The wire might be fine from an amp capacity point of view, but from a voltage drop point of view you aren't getting any value. Huge problem with OEM systems on RVs. Batteries, inverters, solar charge controllers & converters are often quite a ways from each other & dealing with a lot of voltage loss. Ideally all of those components are right next to each other & have much thicker cable than you'd expect for the amps running over them.
I am well aware how electrons work and what it will take to do what I want. I am expecting to run anywhere from 2-00ga cables and use an Anderson type connector. The second alternator will be on the engine. Pretty certain there will be DC/DC converter too.
At this time, it's an idea in my head. When it's that time to do something, I should have it well sorted out.
I dug into the power panel today and identified the current converter charger as a WFCO 55A unit. We purchased a 45A Progressive Dynamics converter with the pendant with model number PD9345.
I hope to have the battery and converter installed in the next couple of weeks as long as my other projects cooperate.
Finally had a spare moment to register the battery and log into the BT app. Pleased to see the cells are balanced and the SOC is well within my storage minimum.
For those looking to go LiFePo4 battery, there is a product that can integrate lead acid and LiFePo4 batteries together. So you don't have to give up lead acid batteries (or their battery chargers that you probably already have installed, see link below.
Even if you don't necessary want or need the extra amp hours of a lead battery, the bank manager product allows you to leave the charging system (including any solar or vechicle alternator charging too) in place and have it function/ play nice with the Lithium.
Here's a page talking more about the Bank manger product and has links to some youtube videos about it too. Yeah, its primary meant for boats/ yachts, but the batteries don't know if they're in a boat or a land based RV.
Pleased to see the cells are balanced and the SOC is well within my storage minimum.
You can't accurately check the balance when the batteries are half way. It's checked at top or bottom. There are two camps that say what is best. I prefer top balancing vs bottom balancing. Google it because that is a deep rabbit hole.
You can't accurately check the balance when the batteries are half way. It's checked at top or bottom. There are two camps that say what is best. I prefer top balancing vs bottom balancing. Google it because that is a deep rabbit hole.
OK, that sounds good.
Once the Progressive Dynamics converter charger comes in I plan to plug it into 120v and let it do it's thing to the battery until I am ready to install it. I am hopeful and confident the cells will balance over time if they are not when the capacity is at 100% SOC.
If not, I am sure the BMS will do it's job during use of the battery with various loads on it to balance the individual cells.
Rezvani's Latest Post-Apocalyptic Monster Is a Ford F-150 Raptor Underneath
Slideshow: Called the Fortress, the 850-horsepower pickup combines Raptor underpinnings with military-inspired features, survival equipment, and a starting price of $285,000.
