Victron Energy Battery Balancer

Works great!After about a year my 2S3P Lithium battery configuration (six 12 V batteries with two batteries in series, three series in parallel for a 24 V system) had started to get out of balance. I used three of these balancers (one for each two battery series) connected through a fuse panel and have had no battery problems for the last two years.

These are very important to Lithium Battery Banks. I found 3 of these with 12-8D Lithium Ion Battery's work flawlessly after a period of 2 weeks from setup. 44,000 watts of Battery Backup.

This thing is perfect, it balances my 2x series 12v 200ah Lifepo4 setup as expected. I did a full discharge overnight then full charge today, now both batteries are sitting at the same voltage. This will extend the battery life and ensure I get full capacity when needed.Did some initial testing with a charger to see that the LEDs would light up as expected when the delta exceeded the voltage for each battery.

As I am a fan of Victron, this is one of the items I will give a negative review for. Per the manual as well as the advertisement in the product page, this item can be used in a 48v series configuration of 4x12v batteries. It states you have to purchase 3 in order to do it and provides instructions on how to configure it. I was hesitant because 3 of them makes it about 2x as expensive as buying any of the other units on amazon that will balance all 4 batteries at once.The reason for the 1 star is because the manual does not state how battery balancing works in a 4S series. In a 2S it would work just fine. This balancer only ever balances 2 batteries. It compare each one its connected to and balances them out. Forget the incredibly high voltage required for these to even turn on. Other reviewers have already posted the negatives on that. In a 4S, you need 3 units because the first balances battery 1 and 2, the second one balances battery 2 and 3, and the third one balances battery 3 and 4. The manual would have you believe that the balancers may communicate with each other somehow, but they dont. So battery 1 and battery 3 and 4, Battey, 4 and battery 1 and 2, etc, they dont know about each others voltage. In theory this would work, but im my case, almost always this will balance 2 batteries somewhere, but the ones farthest away end up over .2v off from each other.For example, Batt 1 - 13.50v, Batt 2 - 13.58v, Batt 3 - 13.66v, Batt 4 - 13.74v. If you look, no 2 batteries directly next to each other are off by .1v or more, so balancing will never happen. Batt 1 and Batt 4 are .24v apart. I have noticed that sometimes, the voltages are so off from the left to the right side, that the voltages on the low pair dont always reach a high enough voltage to even turn on in the first place. Sometimes because of the differences, the Internal BMS of the batteries kick on and shut down before the balancers even start working.For a 2S I would recommend these. In a 4S, these are a money pit.

Fantastic charge controller! Puts you in total control of your battery charging, maintenance, and lifespan preservation. The only thing is that the Bluetooth signal is not strong so you have to be close to the controller, but thats no big deal and maybe even a plus.

Even in a modest series - parallel battery arrangement, this is so vital. Of the components I have assembled in ...the current solar chain... this may be the most interesting (cool) device to watch work... by its very principle of operation. I feel good using this from the beginning with my fresh set of batteries, to see it balancing everything safely, while ensuring increased system utility and longevity. Tightening up the chain, counting ; in 1/10s of a volt... almost there.

Waiting for an installer.

I needed to balance a 4 in series 12.3V LiFePO4 Batteries with built-in BMS. Since the batteries were not being charged/drained equaly for some reason, the BMS in one of them would kick in prematurely and bring down the whole thing. (Was looking at the charger and inverter until I figured this out). So I've been trying battery balancers. Victron Solultion was the most expensive with the need for 3 for 48V system!Lessons Learned (Let's start with CONS)* These devices ONLY KICK IN AT 27.3V Total voltage for 2 batteries. My BMS was kicking out at 13.3V so 2 would never reach 27.3V I had to force my charger to go beyond recommended to have these kick in and balance. I wish we could have a way to choose a lower point to start.* The Victron devices don't come with any cables. You have to buy/make them. I built my but it was time consuming and hard to install.* Adding an extra set of connector lugs to batteries is not always feasible as the battery screws might be too short, so you can't have too many things plus washer and clip. My system being 2P4S , I have a lot of cables and connectors for the MPPT charger and Inverter, so I needed to get longer screws and bigger washers. Should be easier. The end result was a messy spaghetti of cables all over the place - Started so nice and organised* They have a large heatsink in the back and they get used and hot. I'm worried about mounting them on a wooden panel I have my cable connectors on.Pros - as of now* Once I forced the charger to try to go beyng what was stable before, these kicked in and started balancing between 2 sets.* The Victron devices come with LED status light which is waaaay better than the much cheaper version that can handle 4 connectors (built-in) but give you no indication.Will keep them and supervise until the return window gets closer. I need another set for a much bigger project and want to make sure these keep on working. Ugh , 3 more to buy.