This one takes a 14.6v charge (as we'd hope for) and normal operating voltage of 12.8 (also what we're looking for). Be careful of one that charge 12v and operate 12v, those typically are rated 12v to 9v discharge.. Being we'd only get about 30-40% usage from them.

This one is 80ah and charges at 10amps. I'd have to setup charging accordingly. Build in balance charging and wall-wort charger included. Price shown is shipped.

http://www.aliexpress.com/item/4000270680508.html?spm=a2g0o.productlist.0.0.1d4a4a70aVBKrC&algo_pvid=923f6d5a-cfff-485b-9161-451323a5196c&algo_expid=923f6d5a-cfff-485b-9161-451323a5196c-29&btsid=5873e86a-39fc-414f-87c6-1057c158226c&ws_ab_test=searchweb0_0,searchweb201602_9,searchweb201603_55 - http://www.aliexpress.com/item/4000270680508.html?spm=a2g0o.productlist.0.0.1d4a4a70aVBKrC&algo_pvid=923f6d5a-cfff-485b-9161-451323a5196c&algo_expid=923f6d5a-cfff-485b-9161-451323a5196c-29&btsid=5873e86a-39fc-414f-87c6-1057c158226c&ws_ab_test=searchweb0_0,searchweb201602_9,searchweb201603_55

http://www.aliexpress.com/item/32976417259.html?spm=a2g0o.productlist.0.0.4558e3b4fDRbHr&algo_pvid=8f74ace1-87d3-4363-acc9-1beb9d88a615&algo_expid=8f74ace1-87d3-4363-acc9-1beb9d88a615-12&btsid=2baa9432-0c21-48d5-9f86-b2b5d15d32f1&ws_ab_test=searchweb0_0,searchweb201602_9,searchweb201603_55 - http://www.aliexpress.com/item/32976417259.html?spm=a2g0o.productlist.0.0.4558e3b4fDRbHr&algo_pvid=8f74ace1-87d3-4363-acc9-1beb9d88a615&algo_expid=8f74ace1-87d3-4363-acc9-1beb9d88a615-12&btsid=2baa9432-0c21-48d5-9f86-b2b5d15d32f1&ws_ab_test=searchweb0_0,searchweb201602_9,searchweb201603_55

Originally posted by crazycoyote I quit buying directly from China, I don't trust dealing with them. In June I ordered 2 electric folding Trikes at $199.00 each, and waited 4 weeks for delivery, the package came, inside were 2 face clothes. Thank God I paid with a credit card, 4 more weeks, I got my money back from Visa. Not a good deal.

You have to be really careful about batteries from China from what I hear.  They use cheap, off-brand cells, cheap BMSs, and since Lithium batteries are Hazmat, there's no sending them back.

As for those e-trikes, you can't get one decent bike battery for $199!

Caveat emptor.

TT

My concern that on the trailer tongue that bouncing will dislodge the plates in the battery and short out.  Personal experience with batteries.

1.Do not throw battery into water or make it wet
2.Keep the battery away from heat source
3.Do not throw the battery into fire or heat the battery
4.Forbid to hammer to trample the battery
5.Forbid disassembling the battery in anyway

First, weight is the key item to me. I actually loose 100lbs of battery weight with minimal loss of amp-hours. The battery move move inside, reducing cable length to the charger and panel, also protecting it from excessive temperature. The Lithium can be brought into my home during the winter and used as emergency power bank (no off gassing). Cost for me is $160 more than what I bought my dual 6v's for.

As for buying from China, I've had good experiences buying through Aliexpress and Alibaba. I do recommend that you know what your buying and 'read' all the spec's carefully. I also check through all the forums I belong to and see if anyone has bought the product (or from) before. One of these batteries has been purchased before (The GTK)

As far as buying batteries with cheap parts.. Don't have to go to China for that to happen.. Some of the best Lithuim Ion batteries are made in China. So, yes, there is good and bad being sold there. Know your product and research them.

I mentioned this above, yet I don't intend to mount to the tongue. No reason to. The reason your Pba's are out there is because they're too dangerous to have inside.

Lastly, Yes weight is the largest concern for me. I know what my power usage is (I boondock a lot) and I know what my recovery is so I know I can comfortably move to a 80ah battery. Every battery has a limit to cycles before they break down. How you cycle effects the life of the battery. My old LA solar battery bank was purchased new. 2 year limited warranty, said they would last 5-7yrs (lucky if I get 10yrs) and they lasted 17yrs. Cycling is key to longevity. Same for the Lithium battery. 

I passed this along for anyone researching or looking for a Lifepo4 and wishes to save $$, here's a way.

Okay, I'll bite... It's still a wattage thing..??!!??

Not impossible. Look at any smartphone or laptop, it shows a pretty accurate indication of charge remaining, and that battery is a lithium battery with a flat voltage discharge curve.

The technology is just different, that's all. You can buy li-compatible coulomb counters or li-compatible amp counters (battery monitors) that will keep track of the energy stored and energy used.

Originally posted by Olddawgsrule Every battery has a limit to cycles before they break down. How you cycle effects the life of the battery. My old LA solar battery bank was purchased new. 2 year limited warranty, said they would last 5-7yrs (lucky if I get 10yrs) and they lasted 17yrs. Cycling is key to longevity. Same for the Lithium battery. I passed this along for anyone researching or looking for a Lifepo4 and wishes to save $$, here's a way.

Any tip you can pass on to save money on batteries be them LA or Lithium I'm sure is much appreciated by all on this forum. It also reads to me as you did your homework on manufacture spec's and vendor to buy from in China. Your more then right allot of the Lithium and Glass Mat batteries we buy sadly do come from overseas.

I can more then see the advantage of Lithium batteries if you have the money to spend on them I say I go for it, especially if you do allot of boon-docking. Yet, here is my counter argument to you of Lead Acid verses Lithium. Other then weight savings, no argument there your win hands down. Your said from two lead acid batteries you got 17 years use out of them, which is exceptional. Though even at ten years life span if you divided the cost for Lithium per year and then Lead Acid you tell me which is more economical to use not factoring in the few pound of weight savings? Not to be crass but please do convince me and everyone else here that it makes economical sense to trash our Lead Acid for Lithium batteries.

Please do understand, I'm a longtime LA battery guy. Yet here comes a breakdown. If you want a battery to last, for years, water regularly and cycle carefully.

A standard LA 12v battery (marine). Let's work with a 575 CCA or roughly 90ah. To cycle for endurance it should only be drawn to 75% of SOC. That puts us at only 22.5amps of usable power. A Duracell will cost you $95. You get 10% off for online purchase, now $85.50. What's that break down to? 

It is said, AGM's and Gel's can be drawn deeper, yet I 'read' only another 5-8% or so. Kinda matches out in cost per usable amp when you factor the addiditonal costs of these. Only what I read mind you.. I have no first hand knowledge on these.

Now Lithium, I just bought a 60ah for $225 shipped to my door. Lithium is rated differently as in it's rated to cut-off voltage. This gives me 54ah usable and a cost of 

All in for my dual 6v's Right around $250 (batts, cables, box and trade-ins). I determine my usable at 105ah. Here's the deal on Batteries!

$2.85 a usable amp (No trade factored $50 added to cost)

It's not 2-3X the cost when you look at as 'usable' ah's.. 

Then there's the Battleborn folks. That's 400% higher per usable amp. Now there's your "I can buy several LA's" for the same cost. 

Huh?? Care to elaborate a bit?

Interesting side note. The EPA considers 33.5 KWH to be roughly equivalent to 1 gallon of gasoline. That means that an SR+ Tesla Model 3 with a 60 KWH battery has roughly 1-3/4 gallons in the "tank". The amazing thing is that it can go almost 250 miles on that. That is approximately 140 miles per "gallon".

Well, now I have a clue as to what you were implying. I agree with Glue on this.. Wattage is 'power' and watt hours is power over a period of time. 

Again, thank you and well said. 

I deal in wattage mainly to track what is used and what is replaced. Dis-charge/charge cycle. My meters track this for me as watt-hours. I would be close if I tracked amps, yet as you say, wattage changes according to solar in voltage and battery out voltage. Much prefer tracking with wattage.

Also much easier in a power audit when you have both AC & DC appliances. 

... and I still prefer using watts. Precisely because amps will vary by voltage. Unless the load is purely resistive, the amps will go up as the voltage goes down. This is particularly noticeable with lead-acid batteries because their voltage changes with their state of charge.

Thanks for the correction. 

Which loads are constant power (current goes up as voltage goes down)? LED's aren't, water pumps aren't, fans aren't. Those are the main 12V loads in the trailer. 

The reason for working in amp hours is that it makes load calcs, battery sizing, and solar sizing easier, not that you can't do it either way. That's how the off grid solar industry does it and why. If you want to work in watt hours that's fine too, you just have to be careful to apply the correct conversion factors for battery round trip, charger, and solar array efficiencies. No need for a debate about it I don't think. 

There are a couple of don’ts with Li. Do not overcharge, ever. Do not use them at cold temps. Warm them up first. Don’t discharge them 100% (that applies to PbA’s as well of course).  posted by OFFGRID

Here I sit with my pair of nearly 9 year old 12v Interstate group size 24 deep cycles, considering the Lithium until I read the above post by Offgrid.  So . . . . do not use them at cold temps.  Hmmm, for the majority of the time we have camped with our 177 over the past nearly 9 years the bulk has been in the shoulder months (when it is colder) and where electricity is not available.  So if and when these give up the ghost it looks like I will go back the the LA style, but maybe look at a pair of golf cart batteries instead.  For the most part we change out each battery when it gets to 12.2 volts, hence that may be part of the reason they have lasted as long as they have.  Also regular cleaning on top with baking soda and keeping an eye on the water levels.  

Being in the golf industry for over 40 years I have found it interesting how Yamaha, about 6+ years ago went to the 48 volt system.  No, they do not use 4 12v batteries but 6  8v batteries.  Hopefully there will be enough demand for the 6v ones (like the old 36v electric carts had) so that they don't become discontinued.

That being said if there is no other compelling reason to make the change (reducing weight and or increasing capacity) then sticking with PbA and all your existing charging gear makes economic sense. The 6V configuration is common in the RV and off grid solar world too so I think there's not much worry it will get discontinued anytime soon. 

Well, you don't wish to over-charge a Pba either.. that's called boiling the battery. 

Li is more sensitive to cold where Pba is to heat. Both batteries types survive best at room temp, 68F or 20C. It is stated that every 8C or 46F increase you cut the life of the Pba in half (I assume same is true with decrease).

Lithium now has the advantage in warm weather climates.

It is also stated that a Pba will loose capacity in colder weather. Stated that at 32F or 0C you've lost 15% of your battery capacity. If your camping at 0F or 18C you've lost almost a 3rd of your battery capacity

Neither really likes cold weather.

The additional benefit to Li is it 'can' come into the living space and operate normally with no hazard. Again, it can come into the house and operate there as a UPS or Backup power.

Going Li is a choice to be made by ourselves and our own intentions. What works for me, may not for you. My hesitance was multiple: Cost being #1, verifying my power audit as to how we camp & what we actually use and finally weight. 

For me, it now makes sense.