Best battery review I’ve seen. You will be surprised.

Good stuff, but, I think the general consensus has always been that lithium is less expensive when you consider “life cycles.”  Most folks (including me);are sticker shocked on the upfront cost. I opted for 2 6v flooded.

Very interesting. I guess it's good I was ignorant of this info when I purchased our two 6v GC flooded batteries. Though I do regret the weight, I don't regret the initial investment savings.

I wonder how long the heating elements are warranted for. Seems they could be a life-limiting feature for the heated Battle Born batteries, unless they're well made.

I believe the manufacturers estimates for number of possible charge cycles as tested using 20h assumptions, etc.

But it wasn't clear from the video when doing the 8A or 80A discharge testing whether they were concurrently charging as if a solar system was present.

The presenter correctly pointed out that AGMs that are taken to well below rated 50% capacity, and not immediately recharged, have a shorter number of remaining cycles. That's been noted several times on this forum.

But I never use a continuous 8A or 80A discharge rate.  Only under cloudy conditions do I take my AGM battery bank down from 100% to 90% and then not get out of bulk for several days. I would never take the bank down to 50% or 40% in those conditions.

Much more often I'm using a few amps sporadically for the fridge, or a fan. And then occasionally running 50A for appliances, but usually in the presence of strong solar.  So the Victron controller output shows a bulk, absorption, and float phase for every single day.  And it's discharge a little, charge a little, discharge a lot, charge a lot throughout the day, with the only long term low discharge being overnight.

I didn't see that this is how the testing was done on the video. So I don't yet have a warm fuzzy feeling that this was real world testing

I used to have two 125Ah batteries for my 2017 T@B plus a small independent original flooded battery, and now I have just three 125Ah AGMs as of last year.  I'm not a full-timer yet, but have taken dozens of trips each year.  So far haven't seen any degradation of the bank, and would feel safe pulling the 375Ah down to 60% (150Ah) if in strong solar conditions. For $750.  I'd need to spend $1500-2000 to get the same from two lithiums.  I'm only at four years, and maybe the bank will die at six... versus two battleborns would go to ten years.

But I'm not convinced that in real world conditions where a person has 200W solar with 200Ah batteries... or 300W solar with 350Ah batteries, whether we know in real RVs with prudent owners and good battery monitoring whether lithium and AGM might both turn out to have six or eight year lifespans.

I am glad we have so many owners opting to be beta testers for the lithium batteries.  We will have good, real world experiences to offer forum members.  There are so many ways that owners use their campers and batteries that a one-size-fits all mod is not yet apparent.  Hard to justify the cost for owners who predominantly camp with shorepower.  

I find it hard to justify the cost over 2 6v  GC's.  I'd only switch to AGM or Lithium if I were moving the batteries inside.  Out in the tub, I don't have to worry about them being stolen.  I'm kind of hoping someone will steal the GC's in a year or so , so I don't have to lift them to get new ones.

db_cooper said:

I find it hard to justify the cost over 2 6v  GC's.  I'd only switch to AGM or Lithium if I were moving the batteries inside.  Out in the tub, I don't have to worry about them being stolen.  I'm kind of hoping someone will steal the GC's in a year or so , so I don't have to lift them to get new ones.

It's probably hard to justify lithium for a lot of people. For me, weight was an enormous factor. People tend to forget about that. 

From everything I read, lithium batteries are only truly compelling from a cost perspective if you keep them for a LOOOoooong time (years).  At that point they totally are worth the investment because they simply last longer.  But I think people overestimate how long they'll keep their trailer.  I find it amusing how Patrick from the Travels with Delaney youtube channel spent >$2000 on 100Ah of Battleborn, new converter, etc. early in 2020 only to sell his trailer a few months later lol.  And that guy goes through trailers like candy - he's on his 10th trailer in 15 years, so he should've known - who knows, maybe he got some of that stuff for free - just speculation  

Anyways, I'm completely happy with AGM.  You can actually take them down to 20% charge on occasion very safely without permanent damage - granted, the lifespan at repetitive 80% discharges is around half of the lifespan at 50% discharges, so there's a bit of a hit, but the fact that you can safely on occasion go down that low negates one of the lithium arguments, and I'd rather replace the cheap AGMs every few years than go all out on lithium.  I think I'd rather spend on a solar upgrade to enable better boondocking.. not saying there's anything wrong with going to lithium, just seems pricey..

I needed the additional tongue weight the 2 GC batteries provided to offset my bikes on the back.

@webers3, A group 31 size battery fits in the tub with no problems. The Renogy 100AH AGM is that size. We own one and would purchase again.

We have a group 31 AGM here at the house for our sump pump and I can't lift it - It's over 70lbs. I'll admit that I have lady arms, so the group 24 lithium weighing in at 23 lbs gets two thumbs up from me! I guess one doesn't really need to be able to lift it, but I like having the option.

Good point Roger, I was also confused by some of his claims, your graph shows a more accurate look at a AGM discharge and the voltage levels are what I has assumed they would be at the various levels of discharge.   Thanks for posting it.
cheers

@rh5555 fellow nerd here - love the graph. I still wonder how it's possible to even remotely rely on those onboard 4-level battery readouts most rigs have.  I suppose if you just plan on checking before you travel and the battery is rested, it can give you a coarse approximation. But once you start using it, all bets are off.  Battery monitors are an absolute must in my mind, especially since I do plan on (vary occasionally) taking my AGMs below 50% SOC but still want to keep them in a safe range and ensure they last more than just a couple years. 

@ColoradoJon, like you, at this time I cannot justify the cost of lithium. I did get dual 6V AGM batteries, and by the time these need replaced, either the lithium or the newest battery type should be at an affordable price.