Time for a battery upgrade?

AnOldUR

Talk me off the ledge or push me over.

We bought two Vmax 125Ah AGM's about a year and a half ago. They still have lots of life in them, but now that lithium prices have dropped I'm thinking about switching. My contrived justification is that my basement staying dry relies on a sump pump. I'm thinking that the AGM's would be a good way to keep it running for a while if the power goes out. The other thing is weight. We're now at over 140 pounds (compared to 50 pounds for the lithium) of battery weight in our tongue box.

We recently purchased a Dr. Prepare 100Ah LiFePO4 to power a cooler in our TV. So far very happy with the quality and function. I can get two more for a little over $600 delivered. Any opinions on if it's time to take the plunge or is it better to wait for better prices and improved products?

Sharon_is_SAM

Well, you should have a battery backup on that sump pump (unless you have a natural gas geni).  And maybe you need to lighten your tongue weight (by replacing with the lithium in the tongue box you lose 90 pounds of contributing weight to your tongue weight).  If you do that, make sure that tire on the back isn't making your tongue weight too light.  (I think the check is already written!)

VictoriaP

My one issue with lithium is winter charging. If you’ll never have a need to charge those Dr. Prepare batteries during below 32° temps? Sure, they’re probably fine. If I lived in a warm climate, I’d consider it.

But for me, the thought of being out on the road in midwinter, or even at home during a power outage, where the Tab becomes my escape pod, and being literally unable to charge? Not acceptable. And I’d rather pay the extra for a battery with a built in heater by a known reputable company than a cheaper unheated battery from a “rumored to be made by” company with known customer service/warranty response issues, where I have to cobble together my own heating setup.

Which is why I haven’t personally made the switch, because I can’t justify it so far. But everyone’s needs and risk tolerance are different, and it may be a perfectly fine solution in your case.

AnOldUR

Sharon_is_SAM said:

If you do that, make sure that tire on the back isn't making your tongue weight too light.  (I think the check is already written!)

Because of our large truck box up front, we're toward the top of the 10-15% recommended tongue weight even with the back rack loaded. Removing 90lbs would get me closer to the bottom end and probably be a better fit for our short wheel base two door Wrangler. (The checks not written yet, but it won't take much convincing.)

The lack of heating that you (@VictoriaP) mention is less of a concern although maybe it should be. We have no plans to winter camp where the temperatures won't warm up enough to charge during the day, but that's still a risk to consider before making a decision. At least the low temperature cutoff should prevent damage.

Slackers

Make sure the lithium BMSs have low/high temp shutoff? Just asking because a cross-country tour may find you camping in temps ranging from low 30s to 100+.

pthomas745

It is the lithium battery that cannot charge below freezing:  the actual inside of the battery itself.  There are many ways to insulate a battery, like blankets or covers.  A battery in use will actually create its own heat. 

To get the cells of a lithium battery below 32 degrees may not be as easy as you think.  Will Prowse explains this better than I can.  He also has videos about how to make your own heating pads, if that is the direction you want to go.

https://www.youtube.com/watch?v=EaiwxDUY9ho

I have a lithium.  I didn't "need" it, either.  But, it was time to change out the stock battery due to its age.  With well reviewed lithiums now under 400, and not living or camping in very cold weather, and wanting to play with a new toy I bought an AmpereTime.  It does not have low temp charging protection, but my Epower solar controller has a simple low temp sensor that will do the job, if I ever need it.  The lithium was a good purchase (so far) and it has been interesting to learn about them.  I have a propane fridge in my 2017 that I have had some issues in really hot high altitude situations, and with the larger lithium I can now carry a small portable fridge.

The low temp issue has many easy work arounds.

Yoshi_TAB

Hi,

If your able to move them inside, when the Alde heats up the cabin, they will be above 32 pretty quickly and can be charged.  I don't know about all Li batteries, but most can be used/discharged  in cold weather.   Once they get above 32 (or there abouts), the BMS will allow charging.

You can also get temperature controlled heating pads that are not too expensive.  Amazon.com: Facon 8-1/2'' x 5-1/2'' Silicone Battery Heater Pad with Thermostatically Controlled, Automotive Electric Silicone Battery Warmer Pad, 120V, 60Watts : Automotive

I was also on the fence for the same reasons, we don't camp in mid winter but do face a lot of <32 conditions as @Slackers points out for many of the places we go.

Good luck with your decision...

AnOldUR

Yoshi_TAB said:

I was also on the fence for the same reasons ...

I probably should know this from your previous posts, but what did you do? Lithium? Which brand/model?

Yoshi_TAB

Hi,

I purchased two of the refurbished Lion batteries.  They were about 30% discounted.  I'm in the process of installing them inside along with an inverter and transfer switch.  I'm almost done.   They only sell 100 Ah size.  I felt ok with buying the refurbished ones because in my conversation with Lion, they said there was nothing actually wrong with them, but they are batteries that were taken to various trade shows and demos, and brought back to the factory for full testing.   They may have been used and recharged.  The ones I received were pristine with no marks on them.  I believe they are still available along with a sale on the non refurbished ones.  I've emailed Lion a bunch of times with questions about the BMS and other things.  They were very quick with answers.  They have a lot of info. on their website if your interested.  Not just about their batteries, but about lithium battery technology in general.  They are very light, about 23 lbs.

SLJ

Prices have dropped enough for me to switch now from AGM to lithium. I'll be switching this winter. If you use your T@B in winter weather you can get lithiums with built in heaters. Mine are inside my 320. Will have room enough for two 100AHs under the bench.

AnOldUR

If/when I move to lithium in our T@B, I'll want to justify it with the sump pump backup power. Not exactly the perfect place to ask, but there are experienced people here. Any advice on what I'll need to make this work?

My sump pump is 3/4HP. I measured its draw at 700W and 6 amps while running. I'm looking for an inverter charger to keep the batteries topped off and switch to 12V if the power is interrupted. I emailed Renogy about this one. They say it will work, but looking for second opinion or to know if there are better options. Will I need anything in addition to the inverter charger for the pump to run on house power until there's an outage?

https://www.amazon.com/gp/product/B01MS9EI8Q/ref=ox_sc_act_title_1?smid=A2L77EE7U53NWQ&th=1

elbolillo

AnOldUR said:

If/when I move to lithium in our T@B, I'll want to justify it with the sump pump backup power. Not exactly the perfect place to ask, but there are experienced people here. Any advice on what I'll need to make this work?

My sump pump is 3/4HP. I measured its draw at 700W and 6 amps while running. I'm looking for an inverter charger to keep the batteries topped off and switch to 12V if the power is interrupted. I emailed Renogy about this one. They say it will work, but looking for second opinion or to know if there are better options. Will I need anything in addition to the inverter charger for the pump to run on house power until there's an outage?

https://www.amazon.com/gp/product/B01MS9EI8Q/ref=ox_sc_act_title_1?smid=A2L77EE7U53NWQ&th=1

I purchased a Wayne WSS30V dual sump pump and have it connected to an Interstate AGM 100Ahr battery. Neighbors all around me have had their basements flood with spring rains and other big storms. This system has been bulletproof for me.

bergger

Sharon_is_SAM said:

Well, you should have a battery backup on that sump pump (unless you have a natural gas geni).  And maybe you need to lighten your tongue weight (by replacing with the lithium in the tongue box you lose 90 pounds of contributing weight to your tongue weight).  If you do that, make sure that tire on the back isn't making your tongue weight too light.  (I think the check is already written!)

On the flip side of tongue weight being too light.  After NuCamp  the 400 made adjustments to remedy the very heavy tongue weights in the earlier models it looks like they are again over 400lbs.  The 2023 boondock is listed at 407 dry tongue weight.  With propane and other odds and ends in the tongue box it won't take much to get close to or exceed the 15% mark.  I'm sure switching to lithium had a lot to do with that since the 2021 was listed dry at 328lbs and the 2022 at 336lbs, both with dual AGMs.  

Sharon_is_SAM

Wonder if the bunk bed has added to the weight at the front of the 400?  That and less weight in the rear from the lighter weight lithium batteries as @bergger suggested.

bergger

@Sharon_is_SAM I never considered the added weight of the bunk either.  I'm sure both changes contributed. 

kottum

It's the loaded weight that matters.  I would think these would load heavy, or could be loaded heavy behind the rear axle, mitigating some excess dry hitch weight (weighed at the ball coupler, not the tongue jack).  

That said, for stability you always want to load heavier weight gear over the axle as much as possible, not at the extreme front or rear.  Look for 10% to 15% of trailer weight on the hitch ball with the trailer level or slightly nose down.

On a dual axle trailer you want the trailer dead level to equalize the load on the axles and tires.  On a single axle trailer such as our Tab, slight nose down is okay.  Even better if the hitch weight is on the light side of 10% to 15%.  

According to people in the hitch business I have met along the way over many years of towing single and dual axle trailers.

richardspahn

October towed a 23 Tab 400 BD with 4 lithium batteries upgrade from Austin, Texas to San Diego 65-75 MPH behind 2021 F-150 Hybrid with no weight distribution hitch or sway bars...No issues.. in fact, best trip towing I've ever had.

Denny16

Richard, once you reached California, you need to slow down to 55mph, or risk getting a ticket.  You will find your mpg will also increase once you slow down to 55/60 mph.  
Cheers