Visit our Popular Forums

Kanusport · 10-03-2021, 09:32 AM

Hello,
I’ve got a renogy 100ah lifePo4 battery that’s 2 years old and I just ordered a battleborn lifePo4 heated battery for winter streaming. I’d like to have both batteries in a trailer tongue box with the ability to switch between the two. I’d want to use the battleborn when it’s cold and I have to charge yet have the renogy there for backup. I don’t want to wire them together. Is it as easy as a battery switch that switches between the two?
Thanks

uncle_bob · 10-03-2021, 10:23 AM

Hi

To know what's going on with each battery, you will need to wire a separate shunt based monitor to each of them. If you go with a switch, it very much needs to be a "break before make" version. Most battery switches do this, but I'd check the unit you get just to be sure.

The Renogy batteries apparently do some odd things when disconnected. They may not be ideal in this sort of setup. They disconnect / go to sleep when fully idle. They need a blast of current to wake them up. Some ( most??) converter chargers seem to be challenged by this ... The ones they just came out with last week are supposed to be less crazy. I haven't seen any data to back that up ....

Bob

Kanusport · 10-03-2021, 10:48 AM

Quote:

Originally Posted by uncle_bob

Hi

To know what's going on with each battery, you will need to wire a separate shunt based monitor to each of them. If you go with a switch, it very much needs to be a "break before make" version. Most battery switches do this, but I'd check the unit you get just to be sure.

The Renogy batteries apparently do some odd things when disconnected. They may not be ideal in this sort of setup. They disconnect / go to sleep when fully idle. They need a blast of current to wake them up. Some ( most??) converter chargers seem to be challenged by this ... The ones they just came out with last week are supposed to be less crazy. I haven't seen any data to back that up ....

Bob

Bob,
Thanks for the reply. I have had the renogy battery go to sleep and I had to buy a whole other solar charge controller to wake it up because the charge controller on the renogy 200 watt suitcase is not capable of doing it. I’m looking forward to the heated battle born.
Thanks
Sean

uncle_bob · 10-03-2021, 11:48 AM

Hi

It's not my money so easy for me to say ....

I'd just get a second BB and put the Renogy to some other use. Much simpler hookup. One shunt based monitor. No need to mess around with this and that. They should have a pretty good sale coming up later this fall.

Bob

Wazbro · 10-04-2021, 11:09 AM

Yeah, I was going to say you would need a switch that goes battery 1-off-battery 2, Avoid a switch that goes off-battery 1-both-battery 2.
Also with uncle bob's comments about the battery going to sleep when using it as backup, can you get it to wake up with demand (when you need it after other battery is drained)?

jeffmc306 · 10-04-2021, 12:35 PM

You might find what your looking for at BlueSea

I used their 4 position switch when installing a Victron Shunt.

Kanusport · 10-11-2021, 11:47 AM

A little follow up. I received my 100ah battleborn heated battery in the post. I'm moving forward with my idea of having both this new battleborn and my 2 year old renogy 100ah on the trailer tongue. I found a box that will fit in the space bwetween the propane bottles and the front of my 22sportfb. I've ordered the battery box and a bunch of wiring to install the box and have a 3 position switch. So I can switch between the two batteries. I'm using the KISS principle here. The box will have the battery switch, as well as individual SAE inputs to each battery for my 200 watt solar suitcase. I'll update this thread as I move along.
I made a cardboard template that mimicked the battery box.

It looks tight but it's just gonna fit

Kanusport · 10-11-2021, 11:52 AM

It's inches on each side but I think I can make this work

uncle_bob · 10-11-2021, 12:38 PM

Hi

As you run down the road, the A frame flexes ( quite a bit ...). If that shoves the new box into the front of the trailer, you get dents in some very expensive panels.

Bob

waninae39 · 10-11-2021, 12:56 PM

its NOT a good ideas to mix battery types, sizes OEm etc.

each make/model/size reacts differently.

if you proceed , you may find that one battery has a -ve affect on the other

in our sport 22fb, i removed the old lead acid and added the BB lion's under the bed. that also reduced tongue weight

Kanusport · 10-12-2021, 09:32 AM

Bob
I'll keep this updated I think I have enough clearance but I appreciate your advice thanks
Sean

Kanusport · 10-12-2021, 09:32 AM

Quote:

Originally Posted by waninae39

its NOT a good ideas to mix battery types, sizes OEm etc.

each make/model/size reacts differently.

if you proceed , you may find that one battery has a -ve affect on the other

in our sport 22fb, i removed the old lead acid and added the BB lion's under the bed. that also reduced tongue weight

I agree that's why I have the battery switch it's either one or the other not both
Thanks
Sean

Kanusport · 10-12-2021, 09:39 AM

For anyone following I decided on the torklift battery box. It's looking like a snug fit but I think it will work.

https://www.etrailer.com/Battery-Box.../TLA7700L.html

If that doesn't work then my next move will be making my own custom drop in battery box out of steel. I'll rotate the batteries 90degrees and should be able to get two batteries in the space between the spare tire and the lp tanks. I've got the fab skills and tools I was just trying to avoid cutting the trailer angle iron that exsists for the current OEM setup.

I don't want my battery in the camper under the bed. Call me old fashioned but I just don't like the idea of sleeping above my battery. Also I looked under the 22fb bed and there is room for a battleborn but it's tight.

uncle_bob · 10-12-2021, 10:19 AM

Quote:

Originally Posted by Kanusport

For anyone following I decided on the torklift battery box. It's looking like a snug fit but I think it will work.

https://www.etrailer.com/Battery-Box.../TLA7700L.html

If that doesn't work then my next move will be making my own custom drop in battery box out of steel. I'll rotate the batteries 90degrees and should be able to get two batteries in the space between the spare tire and the lp tanks. I've got the fab skills and tools I was just trying to avoid cutting the trailer angle iron that exsists for the current OEM setup.

I don't want my battery in the camper under the bed. Call me old fashioned but I just don't like the idea of sleeping above my battery. Also I looked under the 22fb bed and there is room for a battleborn but it's tight.

Hi

Unlike lead acid's there are very few negatives to having a lithium "indoors". Having them in a heated space actually does some good in cold weather.

Bob

Kanusport · 10-16-2021, 09:28 AM

As I suspected the dual battery box will fit on the front of my 22 sport fb. I’ll be installing it over the next few days.

I’ve got 2” clearance between box and front of airstream.

Rain · 10-17-2021, 01:29 PM

Sean,

Great solution, no need to fret over battery type mixing (your not using it that way), tongue flexing or myriad of other reasons not to implement this KISS solution. Posting it and sharing the box you found, helpful.

turonueve · 10-20-2021, 02:01 PM

Quote:

Originally Posted by Kanusport

As I suspected the dual battery box will fit on the front of my 22 sport fb. I’ll be installing it over the next few days.

I’ve got 2” clearance between box and front of airstream.

Can’t wait to see a pic of the finished product!
-Arthur

Kanusport · 10-20-2021, 09:29 PM

Quote:

Originally Posted by turonueve

Can’t wait to see a pic of the finished product!
-Arthur

Had some time today and I did get the project almost finished. First I will say the box is a high quality product and comes with a lot of items you will need for the install. I chose to mount the box to the A frame of the trailer and the kit had the self tapping bolts and good directions in terms of size of pilot hole to drill. I’ll post more when it’s totally finished but here are a few pictures.

2” clearance

Kanusport · 10-24-2021, 08:58 AM

All done with the install. I mounted the heated battery switch and both solar inputs on one side of box using a step drill bit.

Wanna EB · 11-02-2021, 03:31 PM

Sean,

Thanks for posting your battery mix project.

I am thinking of a similar project. I have two Battleborns on the outside and would like to add two to the inside. I could bring them all in, but would prefer not to.

I was thinking of a 3 way switch as well. Are you using a shunt?, and how did you wind up handling the ground?

Thanks

John