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shagginwagon83 Thu Jul 09, 2020 9:48 am

With the popularity of LiFePO4, I feel we need a thread to consolidate information.

Currently we have multiple great LiFePO4 threads regarding installation in certain areas. These threads below have a great amount of information regarding LiFePo4

New Record? 120 usable Amp Hours under Driver's seat
150Ah LiFePo4 flat under driver seat + swivelectomy

I wanted to make this thread to target overall discussion regarding LiFePo4.

NOTE: This topic is not about other types of batteries. This is strictly about LiFePo4!

Here are some topic of interests in regards to LiFePo4:
Cold weather charging - heating mats
Building your own system using cells and separate Battery Management Systems VS buying a prebuilt solution that has all this sorted out.
DC-DC alternator charging VS having a battery monitoring system control a relay
Battery monitoring systems
Balancing cells before installation
Deals/sources for A-Grade LiFePo4 cells
Shore charging for LiFePo4

These batteries are a great investment and have gained huge traction in the past 2 years.

Just to kick off this thread, I plan to have my LiFePo4 batteries close to my Chinese diesel heater - to keep them warm in the winter. However you could make the argument that the heater's electrical draw should be able to keep the batteries at a warmer temperature.

shagginwagon83 Thu Jul 09, 2020 9:49 am

Somebody in another thread linked these A-Grade cells at a great price

150aH for $500 from China (or $580 from the US)

https://www.aliexpress.com/item/4000316031708.html

shagginwagon83 Thu Jul 09, 2020 9:49 am

reserved

vwhammer Thu Jul 09, 2020 10:18 am

As far as heating systems are concerned this guy goes over a system he built.


I don't know if it is in the skill realm of 100% of the people but he does explain the process pretty well albeit a little monotonically.

shagginwagon83 wrote: Just to kick off this thread, I plan to have my LiFePo4 batteries close to my Chinese diesel heater - to keep them warm in the winter. However you could make the argument that the heater's electrical draw should be able to keep the batteries at a warmer temperature.

Simply using lithium is a good way to warm them up before charging.
As long as you have a temp monitor to keep them from charging until they are up to temp then it certainly is possible to that you may not require a purpose built heater.
You might need a pretty good draw on the batteries before they get super warm but generally any draw will start the process.
Obviously, running the heater, which will also be warming the inside of the van where the batteries might be located, will also not hurt.

dlb154 Thu Jul 09, 2020 10:41 am

I bought the Go Westy 50Ah LiFePo4 and need to set up my "user" setting on my charge controller. Has anyone taken the specs on Go Westy's website and successfully setup their controller on the User settings?


dabaron Thu Jul 09, 2020 11:52 am



this is my setup using the 150Ah LiFePo4 that will fit in the driver's battery compartment.

6 AWG wires are used to connect the starter, LiFePo4, and Renogy DCC50S
8 AWG wires are used to connect the Accessory Fuse Panel to the LiFePo4

the LiFePo4 is powering the stereo, internal lighting, Dometic CRX-50 fridge, kitchen sink water pump, and internal USB and Anderson PowerPole connections (to power amateur radio transceivers).

the Renogy DCC50S has a voltage sensing relay that will not start power draw from the alternator immediately on engine start. no ACR is required, the DCC50S will charge the LiFePo4 if the starter battery is at the correct voltage. the solar panels will first charge the LiFePo4 and then trickle charge the starter battery. getting stranded with a dead starter battery should not happen unless the starter battery has failed.

this is a compact and robust system and the cost is under $1000.00 for a system using a 200W panel. running the numbers the LiFePo4 can last 96 hours if the ambient temp is under 85F based on a 1.2A hourly draw by the fridge. at 90F, i can squeek out 84 hours before needing to charge the system.

as you can see, this is perfect for long weekend adventures without requiring setting up solar or running the engine. solar in my setup is only needed for longer stationary trips or when power consumption is greater than 1.5A per hour continuous for more than 36 hours... the solar panel can charge the LiFePo4 in the driveway between trips.

the LiFePo4 BMS and DCC50S have temp and voltage protection for the LiFePo4 battery. the battery will not charge at subfreezing (33F and below) temps. i do not plan to use the system at this time in subfreezing temps and can disconnect the system using the two breakers.

this system is over spec'd and can comfortably support the use of an inverter, or the addition of a propex heater.

jimf909 Thu Jul 09, 2020 9:56 pm

i love it. I'm going LiFePo when I can get 200 ah below the truckfridge. I came across that idea and became irrationally attracted to it. The basement of the Westy closet is another possibility. The spaces under my front seats are occupied and I don't want batteries under the rear bench.

shagginwagon83 Sat Jul 11, 2020 7:39 am

jimf909 wrote: i love it. I'm going LiFePo when I can get 200 ah below the truckfridge. I came across that idea and became irrationally attracted to it. The basement of the Westy closet is another possibility. The spaces under my front seats are occupied and I don't want batteries under the rear bench.
Currently my aux battery is under rear bench seat and it kills me wasting that easily accessible room.

I need to drink some beers, read some more lifepo4, and just hit the buy button.

-Dabaron (steve). That's a great setup man. I feel overspecced is under rated for electrical system in these vans.

Luckily I have overbuilt my system to where once I make the conversion to LiFePo4 I don't have to change most of my wiring. Really excited about that.

Do you know if your BMS has a shunt built in? This is BMS I am looking at -

https://overkillsolar.com/product/bms-120a-4s-lifepo4/

shagginwagon83 Sat Jul 11, 2020 7:46 am

Also wanted to note in this thread that GoWesty has a great LiFePo4 solution for a light power user that doesn't want to do their homework! I'd highly recommend this solution over their AGM battery.

Shipping/handling may kill the deal. However myself would like 150-200ah of power in my van.

https://www.gowesty.com/product/electrical/25082/lifepo_aux_battery-50ah

ledogboy Sat Jul 11, 2020 7:46 am

shagginwagon83 wrote:
Currently my aux battery is under rear bench seat and it kills me wasting that easily accessible room.


Totally agree. While I wouldnít want to be without the storage capacity I currently have under there, the loss of that space is a huge bummer. Iím stripping out that whole system today and will be installing everything but the Lifepo4 batteries (which I am still waiting on). Iím going with the Renogy DCC50s and the BMS from overkill solar. Stoked.

shagginwagon83 Sat Jul 11, 2020 7:54 am

ledogboy - Super pumped for you and jealous :D I'm pretty stoked thinking about this upgrade! I really saw a need for a better battery when using my chinese diesel heater.

Do you know if the overkill solar has a shunt built in? I'm looking at the diagrams and where the BMS is inline with the ground I feel like it should. I need to do more research about the overkillsolar. I really like it is programmable and also open source code. Hell he even has his own subreddit for support!

kourt Sat Jul 11, 2020 8:58 am

I'm on my fifth iteration of aux battery setup in my 91 Westy.

Since this is a LiFePO4 dedicated thread, I'll just provide links to the photos of the older SLA batteries:

first iteration, three 55ah SLA batteries in parallel
second and third iterations, one big 200ah SLA battery

Now on to the LiFePO4 stuff. Here's the fourth iteration: one Battle Born 100ah LiFePO4 battery, with Redarc BCDC1240D:



...and now the fifth iteration, two Battle Born 100ah batteries in parallel:



The Redarc is fed by 240 watts of solar on the roof and the alternator.

Why did I go with two Battle Born batteries in parallel? Because I was easily depleting the single battery with my DC power demands (amateur radios, plus comfort things like refrigerator, LED cabin lights, and USB charge ports).

I'm in the middle of a 4500 mile road trip right now and this dual battery setup has been a source of great comfort. I have no capacity anxiety with the dual batteries. On several occasions I have left the van for several days--the last being six days total--with the refrigerator running, with the voltage sitting at 13.3 volts when I depart and when I return. I've never had that confidence with the aux battery system before.

I am convinced the combination of the Redarc and the parallel batteries is what's making this work well.

You can see in the photos that I placed the batteries on their short side, so that the terminals face aft. This is a perfect fit for the rear bench space--no space is wasted vertically in this configuration.

kourt

ockyfib Sat Jul 11, 2020 9:22 am

Hey dlb154,
I'm planning to do the same and replace my std battery under the driver's seat with the GoWesty 50Ah LiFePo4. What charger are you going to be using and does anyone know whether I could just keep using the GoWesty solenoid? I know it charges slowly but that's not usually an issue for us.
Thanks

sphet Thu Jul 16, 2020 9:47 am

Our normal pattern is to camp one night and drive for four hours or more to the next site. Now that we are under provincial lock down, we are spending many days in a single site, so while we really only use the battery for usb charging, cabin light and water pump, I think it's time to consider a second battery.

I would like to use the Renology DCC50S with something like the GoWesty LiFePO4 under the driver's seat. We don't have a DC fridge so our amp hour usage is low. We would only need solar on long-stays, so a portable panel would be the plan. This seems good for my early van where the battery is in the back; I only need to add the charger, battery, fuse box and rewire the kitchen power and cabin light.

What are my options for shore power charging? I imagine I could charge my starter battery, but the Renology would require the alternator signal to draw.

What are other people doing in this situation?

shagginwagon83 Thu Jul 16, 2020 10:12 am

I like Victron's products a lot. Most have bluetooth that allow you to easily update the devices firmware.

The link I sent is for the 15amp model but you can get a 5 amp model for $80 I believe. Note, with any LiFePo4 shore charging, you should be able to set the voltages per battery. I believe the Victron unit can do that.

I'd recommend downloading the Victron app on your phone and 'demoing' this product. It will simulate the actual product without even buying it.

https://www.amazon.com/dp/B07FGGCYKC

MarkWard Thu Jul 16, 2020 10:17 am

I have a Pro Nautic, Pro Mariner installed next to my fresh water tank. It will charge up to 3 batteries. It's hardwired to my shore power outlet. What's nice about this charger is you can actually use your 12 volt accessories while charging. Not all battery chargers support that.




We don't use a lot of power either when camped. I will plug in when its available to extend my propane and the van is always plugged in when it's parked.

No help on the Solar or the LifePo battery.

sphet Thu Jul 16, 2020 10:20 am

shagginwagon83 wrote: I like Victron's products a lot. Most have bluetooth that allow you to easily update the devices firmware.

The link I sent is for the 15amp model but you can get a 5 amp model for $80 I believe. Note, with any LiFePo4 shore charging, you should be able to set the voltages per battery. I believe the Victron unit can do that.

I'd recommend downloading the Victron app on your phone and 'demoing' this product. It will simulate the actual product without even buying it.

https://www.amazon.com/dp/B07FGGCYKC

So you would suggest adding this *in addition* to something like the Renology DC-to-DC MPPT charger? Plug it into the outlet under the sink, and then connect it to the battery, completely bypassing the Renology DC-to-DC connection? Any risk if I forget to unplug my solar while plugging in to shore power?

shagginwagon83 Thu Jul 16, 2020 10:25 am

As Mark stated, you need a battery charging and power supply. The Victron unit has both that functionality.

If you had a smart solar controller then I would say you would be fine to use both solar panel and shore charger at same time. Once it gets to set voltage, both should kick off (or rather maintain the battery)

sphet Thu Jul 16, 2020 10:28 am

Thanks Mark and Brandon; I see now it is two problems to solve. I feel I may have gone off topic for the thread so admins can delete it appropriate.

shagginwagon83 Thu Jul 16, 2020 10:40 am

You're fine. There might be a better solution that utilizes the Renology DC-to-DC that I'm not aware of.



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