batteries and charging

[taliv]

i have a trailer with 3x 102ah batteries that need to be replaced. i'm thinking about ONE 300ah lithium battery. it's really expensive, so i have questions for those who have done similar.

1. is it true that 2000 recharge cycles means the battery is a good investment? i mean, did you actually get a long life from yours?
i don't know how many cycles lead acid is supposed to get, but i can tell you 3 years and around 50 nights per year in my trailer and my batteries aren't what they used to be. if the marketing is correct, the lithium would last me the lifetime of the trailer. 3 batteries x $200/bat = $600 vs $2400 for the lithium. if i replace lead acid every 2 years, that's 8 years before i break even, not counting time value of money. otoh, with the end of the world virus stuff, there's a little peace of mind owning something that will last a long time.

2. can i just swap the cables and continue charging from shore power, solar and the dual battery vehicle alternator? or do i need a fancy special charger for lithium?

3. any concerns with kabooms? spontaneous combustion? in an overland environment i mean



link to battery in question. feel free to suggest better options

PSL-BTP-123000 12.8V 300Ah Bluetooth Lithium Smart Battery | Power Sonic

The Power Sonic PSL-BTP-123000 is Part of our Class-Leading Battery Range. Find Out More Today.

www.power-sonic.com

 

[Flipper]

i have a trailer with 3x 102ah batteries that need to be replaced. i'm thinking about ONE 300ah lithium battery. it's really expensive, so i have questions for those who have done similar.

1. is it true that 2000 recharge cycles means the battery is a good investment? i mean, did you actually get a long life from yours?
i don't know how many cycles lead acid is supposed to get, but i can tell you 3 years and around 50 nights per year in my trailer and my batteries aren't what they used to be. if the marketing is correct, the lithium would last me the lifetime of the trailer. 3 batteries x $200/bat = $600 vs $2400 for the lithium. if i replace lead acid every 2 years, that's 8 years before i break even, not counting time value of money. otoh, with the end of the world virus stuff, there's a little peace of mind owning something that will last a long time.

2. can i just swap the cables and continue charging from shore power, solar and the dual battery vehicle alternator? or do i need a fancy special charger for lithium?

3. any concerns with kabooms? spontaneous combustion? in an overland environment i mean



link to battery in question. feel free to suggest better options

PSL-BTP-123000 12.8V 300Ah Bluetooth Lithium Smart Battery | Power Sonic

The Power Sonic PSL-BTP-123000 is Part of our Class-Leading Battery Range. Find Out More Today.

www.power-sonic.com

Any charger will work as long as it will charge
Bulk 14.4v
Absorb 14.6v
Float 13.6v
They also make specific lithium ion chargers.
A charger large enough to charge a 300ah battery in any reasonable time is probably 20-30A is going to run around $400-500.
If your not getting good life from your AGMs make sure you don’t discharge them past 50% and make sure they are fully charged after use. If they a bowed out on their sides you might be overcharging them.
AGMs
14.6-14.8v charge
13.6-13.8v float
Using start battery in a deep cycle application and deep cycle in a start application will shorten their lifespan.

 

[brian0128]

I went with multiple Battle Born batteries 100ah due to their literature saying 3000-5000 cycles(approximately 75-80% of the battery capacity will remain after 3000 cycles) and their 10 year warranty. They have a page showing the math and it comes down to .35 cents / lifetime amp-hour for lithium and 1.67 cents / lifetime amp-hour for lead acid. I'm assuming AGM is in the middle. At 3000 cycles I'll have these for 15 years.

 

[theMightyGoose]

I'm ordering a camping trailer which comes with 2x150Ah AGM. There is an option to upgrade to lithium but it's a $3k upgrade. I didn't think it was worth it but now I'm reconsidering. I still have the option to order the trailer with the lithium. Starting to think it might be worth the extra cash to do it now.

 

[taliv]

Which batteries are you considering?

 

[theMightyGoose]

I'm not sure about the specs. Waiting for the manufacturer to get back to me. The stock is a 2x150Ah gel battery. The upgrade I believe is a 200Ah lithium. It's all out of Australia.

 

[taliv]

Ok doing some research. Opinions welcome.

new lead acid deep cycle 100Ah would run about $240 and weigh >60lb. So if I replace all 3 of them, I'm spending $720 and still have 180+ lbs.



so options are (see spreadsheet at bottom)
- 2x 100Ah batteries - gives 30% more usable juice than I had when current batteries were new, saves 120lb of weight, and some space
- 3x 100Ah batteries - 100% more juice, saves 90lb of weight, costs $k more than 2x
- 1x 200Ah battery - 30% more juice and saves 110lb weight, but doesn't fit in battery holders, cheaper than 100Ah options
- 1x 300Ah battery - 116% more juice, saves 85lb weight, need new holders, significantly cheaper $/Ah/cyc


fwiw, my usage is
41A /day fridge/freezer, on a 43*C day https://www.nationalluna.com/wp-content/uploads/2017/09/90-freezer.pdf
2.2Ah operating water pump which, even if i showered 30 minutes, and washed dishes 30 min is just 2A / day
bunch of LED lights not worth calculating
2000W inverter which I think would be 17 amp, but gets minimal usage, i'll say 1hr/day for budget so 17Ah?
total is about 60Ah/day
so, 200Ah of juice is 3.3 days with no solar
300Ah of juice is 5 days no solar

challenge is this camper has 3x standard car battery sized 102Ah batteries, and what i assume are custom battery holders which are aluminum rectangle on bottom with long screws and wingnuts that hold a bar on top to prevent the batteries from flying all over when i'm offroading. these battery holders are riveted to the floor of my camper and i could probably remove them but i'm not sure i can replace them. maybe i can. idk. i'd have to learn to rivet, and figure out how to seal the old holes, which i can only reach from above the floor (water tank underneath them).

I like made in USA
battleborn, which is based in reno. dakota is based in ND. 10+ year warranties would be nice, but idk if they're worth anything. prob cost as much to ship the battery back as it would to buy a new one.
smart is mysteriously quiet about where their batteries are made, but claim they have sold quite a large QTY
powersonic is only listed because they're sold by batteryjunction where i bought tons of eneloop and 123 type batteries over past decade. and they have a nifty bluetooth app so you can monitor batteries from phone.


I'm leaning towards smart.
So, $1600 for a 200Ah and a lot of work to build new battery boxes and remove old ones, or
$2000, for 2x 100Ah and a 10 minute easy drop in, or
$2400 for a LOT of juice and a lot of work

What would you do?

 

[theMightyGoose]

I would do the 2x100Ah. A bit more money, but might be negligible once you get into fabricating new boxes and any unforeseen problems related to the 1x200Ah. Biggest weight savings, which can also pay you back in other ways.

 

[smritte]

It's nice to see I'm not the only one who works the math before deciding something. I edge towards simple then what if. I prefer two batteries as long as their parallel (think 6v series). Size isn't an issue to me because I can make my own mounts, If you cant that's a big factor.

After all that, my requirements allow me to run one 90ah battery. I chose lead acid because their not picky on charging, their cheap and readily available. I also have over kill on solar and don't base camp in bad weather (no sun=no solar).

Forgot to add
3. any concerns with kabooms? spontaneous combustion? in an overland environment i mean
Read about lithium batteries and high ambient temps. I live in a desert. One of my buddies had his travel trailer burn to the ground while it was in storage. We had over 100 degrees for a week. The temp inside the trailer got high enough to ignite the batteries. He posted a picture of the battery bank melted. All I can say is WOW.

 

[taliv]

i'm kinda the opposite. while i do go out west a lot, any place within 300 miles of me is going to be covered in trees. my solar input is relatively small and i can expect partial shade. and i camp rain or shine. so i need a bigger battery.

that's what i was worried about on the temp! hmm... the batteries say operating range is up to 140F so I don't know if some sort of damage causes the operating range to be reduced, or if the temp gets higher than that. i flew 100+ times last year for work and every time i got on the plane they asked me if i had any lithium batteries... makes me nervous.

 

[smritte]

the batteries say operating range is up to 140F

There may be different "ranges" depending on battery make up. I never looked into that beyond obsessing over the portable jump boxes and leaving them inside your car on a 110 degree day. That's where research comes in.
Years ago while working at a dealership (80's), I had a customer complaining about his AC. Short version is, over 100 degree ambient temp, thermometer in the car with the windows up. Checked it in the afternoon sometime and I don't remember the exact temp but I do know it was over 140 degrees. With those outside temps, you could get a second degree burn if your arm pressed against metal in the car.
If I get into a situation where lithium's are viable, I will look into temps and what it takes to keep them safe. Enough people run them without issue so there's that. I would be more concerned on my end about where it sat in the summer during our high heat (it gets over 110 here every summer) than i would while I'm out and about.

 

[smritte]

any place within 300 miles of me is going to be covered in trees

Forgot this.
I wish I had the same. I love the forest.