One of the first things I'm asked when I mention lithium batteries to someone is how long will it power whatever they need a battery for? I needed a battery with this capacity for those times when I either have to power something for a short time that requires several amps or for times when I have to show someone firsthand how long something they have like a small cooler can be powered with a battery small enough and light enough for them to easily take with them. I needed a battery I could connect and disconnect quickly with wing screws, bolts, or alligator clips small enough to put in a case and take with me. This reBel battery turned out to be the perfect battery for that purpose.
Like its little brothers, this battery doesn't disappoint. It over-delivers and is pretty impressive. The case is plastic but feels sturdy. The battery has posted one on each end that sticks up from the top with a bolt in the middle. The posts are handy if you want to connect something with clamps for temporary use and the bolt makes it handy to connect a cable to the top of the post. The plus and minus signs are engraved on top of the case making it easy to identify the positive and negative posts easily. The battery came with two long bolts in the posts long enough to attach two cables. Also included were two types of extra bolts. One that you can tighten with a wrench or a Phillips screwdriver and a second set you can either tighten with a Phillips or a regular screwdriver. These are shorter bolts good for connecting one cable. The battery also came with a set of power cables.
The lit LCD display on top of the battery is so handy for checking the voltage with the press of a button. One press of the button turns the light on for about ten seconds. The button sounds and feels like an industrial switch that will easily withstand many presses.
Like the other reBel batteries, this one is a powerhouse. Its max charge current is 12A and the max discharge current is 25A continuous.
Here's a 16.5 amp discharge test I ran twice and got the same results both times.
With no load the voltage was 13.4V. After applying the load and letting the battery stabilize for 30 seconds the voltage was 12.75V. That's not bad considering the load was only a few amps below one C on this battery. If you're wondering why the voltage was so much higher on the 50AH battery? It's because 16.5 amps is still several amps below half the C rating of that battery.
Fifteen minutes, 12.7V.
Thirty minutes, 12.63V.
Forty-five minutes, 12.58V.
One hour, 12.48V.
One hour fifteen minutes, 12.27V. At this point, the current dropped to 11 amps.
One hour twenty minutes, 12.12V. Five minutes later the BMS turned the battery off at 11.1V. As you can see like the other reBel batteries this one also has a very flat discharge curve and stays above 12V until almost the end of its cycle. I like the BMS turning the battery off at 11V because I don't have any reason to go much below 12V. Most of these batteries turn off at around 10V. I don't know if all the 24AH batteries are set to this low voltage disconnect or if mine just happened to be, but, I got the same disconnect voltage when I ran another test.
If you're reading this knowing nothing about batteries you probably wonder if the difference is really enough to warrant the extra cost of a Lithium Battery over an AGM Battery that costs less? If you're wondering what the difference would be if a Led Acid battery was used in a test like the one I did? Here's a video review someone did on an AGM 35AH battery drawing 4.5 amps less than I drew from the reBel 24AH battery so that gives the AGM battery the advantage. The review states it was a new 35AH battery.
There was nothing wrong with that battery. With Led Acid batteries the heavier the load the less AH you can use at 12V. One of the big advantages reBel batteries have over AGM batteries is being Lithium Iron Phosphate batteries you can use one hundred percent of the capacity you pay for time after time without doing any damage to the battery. Whether you draw one amp or the full C-rating of the battery you will get most of its capacity above 12V. I could do the test I ran hundreds of times and get very little loss in capacity. Each time you discharge a Led Acid Battery you will see a loss in capacity. Go below 50 percent and it won't last very many cycles. In the long run, the Lithium Battery costs much less when you consider how many times it will outlast an AGM or Flooded Lead Acid Battery and that's not even taking into consideration all of the safety and protection features that come with the Lithium battery.
If you buy one of these smaller reBel batteries with the LCD display you will notice the LCD on the battery shows a slightly higher voltage than your meter at the output terminals or in your system does. This is because the voltmeter in the battery is measuring the actual cell voltage. In any system, there's always some loss when electricity passes through electronics and cables. For example, at one point in a test on another battery my meter showed 12.77V and the LCD on the battery showed 12.9V. This voltage loss is very minimal and nothing to be concerned about. On the other hand, if you notice a big loss in voltage at your meter it could mean your wire size is too small to carry the load, you have a bad, dirty, or loose connection.
Whether you need a battery to power a small cooler for a few hours, to provide power for lights, a small power inverter for an hour or two, or for other light power use in a small cabin or just about anywhere you need 12V power where you don't have much room this is the battery for you. In conclusion, this isn't a bad little battery! Because of its small size, lightweight, high capacity, and C rating there are many possible uses for it.