PowMr Battery Equalizer 48V - Battery Voltage Balancer,for 4×12V or 8×12V or More Battery Bank Extend Battery Life 1 Year and More, Support Gel Flood AGM Lithium Battery HA02 Balancer

Only negative thing about this is the slight whine it makes. It was noticeable right after hooking it up but over time it became less noticeable. Seems like this isn't unique to this particular balancer or brand though, so I'm not upset about it and knew to expect it when I bought it. As for the balancing performance, it works very well. Within 48 hours of hooking this up my batteries were equalized with the BMS reading within <0.5ah of each other. I actually have two of these running on separate battery arrays and they have both been great. Can't think of any reason to get one of the more expensive balancers.

I have used lithium batteries for about four years on two separate 48v golf carts, one with 4 12v batteries and one with a 48v battery, and over that time I have numerous issues and have had several batteries replaced under warranty. My last problem was the one with the 4 12’s. One or more of the batteries seemed to go down before the others and the cart would stop. When checked all of the batteries proved good. The problem was an erratic discharging which this equalizer handled and the cart has never run better or longer. This a a must product for anyone with a 48v lithium powered golf cart. . Don‘’t think twice about installing it, just do it.

Got this on Jan 15 2026. Worked great since then till a few days ago when the system shut down low voltage and the balancer was very hot, but but not enough to burn you. Left it to see if it would bring things back in line but it stayed that way for a couple days. Then I swapped it into an identical 48v system with the same exact model balancer that worked fine and it got hot again right away. Put the original back and it's still cool like always. Sent feedback to vendor to see if they will help.

It DOES emit an annoying whine as other reviewers have mentioned. It's called PWM whine, and they could fix it by simply adjusting the frequency they're using. I attached it to a bank of 4 12v WEIZE batteries. I woke up a few days later to a dead battery bank. Thankfully I'm using Solar Assistant and ESPHome to track which devices use energy and was able to identify the culprit immediately. Note the "current" is 0 (meaning nothing is using or providing power though the charger/inverter) but the voltage drops and drops. That's the PowMr in action. If I were already off grid (as this testing is intended for), I would be in for, at minimum, a couple crappy days while the system recovered. If I were not using lifepo4 batteries with a reliable built-in BMS, my batteries would have been destroyed. Steer well clear of this piece of crap, and please test ALL your gear for a few days before actually heading into the wild with it. Could save your life. I myself get to sit and wake all my batteries back up so I can get my system going again.

Easy to set up and the wires are clearly marked. After installing, my 12V batteries stay much more balanced. The connectors feel solid and the unit is compact. Works as expected and gives peace of mind for battery health.

Does what it advertises. But if the batteries are pretty far apart it works really hard to balance the batteries. In doing so there is a tremendous amount of heat it creates. I purchased a set of 2 heat spreader that have adhesive to dissipate the heat more efficiently and hopefully vastly increase its life span I recommend any version that looks similar behaves the same way. I would Def buy a heat spreader.

They're easy to use, and they give significantly longer functional lifespan to 48v batteries built out of smaller 12v batteries. On golf cart conversions, these nearly double the range. They encourage even loading of the smaller batteries, and extend their lifespan significantly. They also make it much easier to wake the batteries back up if the BMS disables them due to over-charging; you can use a standard booster box to wake up one 12v battery, and the BMS tries to balance all 4, meaning they all wake up without having to jump each battery separately. They do get a little warm during extended use, but they don't heat up at all when balancing my solar batteries.

So, I had ordered one of these from another seller almost a year ago and it did not work. Thought that these were probably fake or just didn't work very well, or noticeably at all? Well, I never stopped thinking about how badly I wanted my 16(1S2P) golf cart battery array to be balanced because the voltages were all over the place even after a few equalization cycles. So then I saw one of these again and decided to just give it another try. Well... It works amazingly well! I now have 2 hooked up after digging through the guts of the old defective one and repairing it now that I know when they work, they WORK! If you happen to be in close proximity to your battery bank on the other hand, they emit a loud, high pitched "coil whine". Enough to make some people hate them. I for one would much rather my multi-thousand dollar battery bank gets the treatment they deserve for faithfully serving me up my collected solar energy 24/7. Will for sure be getting more of these!