LiTime 12V 100Ah TM Low-Temp Protection LiFePO4 Battery Built-in 100A BMS, Group 31 Deep Cycle, Lithium Iron Phosphate Battery Perfect for Trolling Motors, Yacht, Marine, Boat, RV, Home Energy

Great battery, super light and super functional. Use the battery on my Pelican Bass Raider running my Livescope, Trolling Motor and brake stop. Unbelievable the lightness of this battery, weighing just a few pounds but packing a punch. If you are looking for a solid lightweight alternative battery to the super expensive battery's in the boating market grab one of these.

I replaced two 6 volt lead acid batteries with four of these batteries, wired together in parallel to power the 12-volt system in my 13-foot trailer, including a new 60 watt fridge in. We enjoy remote camping for a week at a time, and need to be able to keep the fridge running while still being free to unhook and go exploring with our 4WD vehicle, without leave all our equipment out, unlocked charging (you know, solar panels, etc.) while we are gone. I have tested these batteries and find that they will last about 6 days before they are discharged to the point that they turn themselves off. (They have internal protection so they won't overcharge or overdischarge and get damaged.)The company has representatives who respond to questions within 1-2 days via email and I have been very happy with their service. When wiring four batteries, it is important that they stay in balance. To do that, I wired all the positives to a positive busbar, and all the negative wires to a negative busbar, using identical length wires (instead of to each other.) (see photo) This keeps them in balance with each other during charging and discharging. (You can also wire them in series in order to increase the voltage, of course, but I needed to stay with my 12-volt system and just increase the battery capacity, so I wired them in parallel.)My only issue is that LiTime's wiring diagram for wiring in parallel does not seem to be correct. They show wiring with a busbar and ALSO wires between each battery which is definitely not necessary and probably also defeats the purpose of using the busbars. When I asked them about it, they stood by their diagram, but their reason made no sense to me. They said the batteries also have to be connected to each other. But they ARE connected to each other via the busbars! I checked with an electrician who said he couldn't see why the extra wires would be needed, but didn't want to contradict the company's instructions. I can't even imagine how crowded the wires would have been if I had used twice the number of wires, LOL! The system is working beautifully by wiring just to busbars.The batteries fit in a standard group 31 battery box and weigh half the amount of a lead acid battery, so I can handle them easily by myself (69 y/o 100 pound female). (I could never begin to lift a lead acid battery by myself.)Changing from lead acid to LiFePO4 batteries is a steep learning curve! We tried to get the help of an autoelectric business, but they said they didn't have any experience with Lithium batteries. You'll have better luck at an RV service place, or study youtube instructional videos. But there are numerous advantages! The LiFePO4 batteries charge much faster, last a lot longer with each discharge cycle, have a much longer life overall, and are half the weight of lead acid batteries!Here is the learning curve part: If you discharge Lead acid batteries past 50 percent of their capacity, you damage them; whereas you can discharge the LiFePO4 batteries down to 20 percent and still maintain their long life. The trick is figuring out when they are getting close to 20-25 percent of their capacity. LiFePO4 batteries have a very flat charge/discharge curve. They stay at 13 volts from 100% (at rest not charging) down to 25% capacity, then drop precipitously. If the voltage reads 12.8, they are almost dead and need to be charged immediately! You need a multimeter to check the capacity, which is read in 10ths and 100ths of a volt, because the change is very tiny until the end. (see page from LiTime manual.) It's important to know to check the voltage with loads removed (i.e. fridge and lights turned off in my case). Also, the voltage drops on the way to the load (i.e. the fridge wiring), so the fridge reads a lower voltage than that measured at the battery. You will have to get used to what your fridge (or other device) says the voltage is, versus what the actual voltage is at the batteries by using some kind of voltage meter. I have been able to develop a feel for the actual voltage vs the fridge reading by checking and rechecking over time. As I say, it is a learning curve.While running, by the way, the fridge says the battery is at 12.4 or 12.8 volts usually. That is normal. The battery capacity is measured at rest. So I just turn off the fridge for a moment to see what it is measuring at rest. Then I compare that reading with what the voltage is at the battery itself. When the fridge says 13.0, for example, the multimeter at the battery says 13.26. If the fridge gives me 12.8 volts at rest, I know it's time to recharge! You'll need to do the testing to know the parameters for your own system to be sure.

I wanted something reliable. I've spent so much time learning the things I need to know, and quite a bit of money for the best components I could afford. When it came to the batteries I wanted to get what are considered by many to be the top of the line, but frankly they are a lot more than I'd hoped to spend. I just can't reason why this many years into lithium battery development it should still cost so much to get a reliable and safe battery with a quality BMS. So I read the battery reviews on Amazon, which I love and rely on but always take with a grain of salt, and then I looked to some solar forums around the net. One in particular dated back awhile and everyone seemed impressed with Ampere Time batteries, and they all seemed way more knowledgeable than myself about it. At less than half the price of the highly rated ones I decided to bite the bullet and take a chance on what might end up being a weak link in my solar system where I really should have invested heavily. My battery order shipped the day after I ordered it and it arrived about a week later across the country from California.On first impression the box was nice and strong, and upon opening the box I found the battery completely secured and cushioned with thick and dense foam inserts. The paperwork, a large 10 page color brochure on the company/product brochure/product manual/and lifetime service card, all came in a thick clear vinyl zip case that reminded me of the type that comes with a new boat. The manual is in color with lots of graphics and is nicely readable and easy to understand. Few companies these days seem to give their product this kind of attention and I was already feeling like I'd made the right decision. The battery has a nice wide soft nylon strap across the top length of it to assist in carrying, even though it isn't a very heavy battery, which also made it easy to remove the battery from the box. Both 100ah batteries I bought were in perfect condition and both were charged exactly at 81%. I've only used them for about two weeks steady so far but they have been working flawlessly on a 600w 36v array with a Victron controller. I've ran a 8000btu LG window air conditioner on it with a 2000w continuous/4000w surge inverter, and I've ran things like a large side by side refrigerator/freezer, my 1250w inverter microwave, a 1500w portable infrared stove, and a large oscillating fan (not all at the same time). The seller has reached out to me more than once to ensure I'm happy with my purchase. Five stars because I couldn't be happier and I have no downside to report. My first impressions were high enough that I ordered two more 100ah batteries, for the max total of 4 allowed in a bank, to help me expand a little. I'm a real customer of this product and I wasn't compensated in any way for this review, if you found this review helpful please click the button.