DALY Smart BMS 4S 12V 200A LiFePO4 PCB Protection Board with Balance Leads, Wires 3.2V Battery Protection Module BMS for 18650 Battery Pack 12V with UART(Smart BMS,200A)

I had a 250 ah LiFePo4 battery that I bought here on Amazon. Well, It’s a great battery, but it malfunctioned. The on-board BMS (battery management system) went bad. Not sure if they want me to mention their name, so I blurred the logos in the photos. But they make great batteries.I could still connect to the battery’s bluetooth and see that the battery had 13+ volts of power, but the terminals were only getting 1.8 volts. I talked to the battery manufacturer and they told me it had a bad BMS. So they sent me a new battery, but didn’t want the old one back. So instead of trashing it, I decided to see if I could repair it.So I bought this high amp Daly BMS. I was able to get the battery case open quite easily. I thought it was going to be difficult. I had seen some YouTube videos where the kid takes power tools to cut the batteries open. But his one had a silicone seal that was easily pried open. I was able to remove the old BMS, careful to remove all the power leads first. Then install the new Daly. It was quite easy. I did have to reverse the direction of the B- lead so it would reach the terminal, but that was very easy. I slid a small piece of thin plywood under the straps holding the lithium sells together, then zip-tied the BMS to the plywood to keep it from shifting around during transport. It was shallow enough to fit on top of the cells and still replace the cover. I haven’t resealed the cover on yet, I will give it a couple of months to make sure it continues to operation as well as it is now.The only thing I didn’t do was mount the bluetooth transmitter outside the battery case. It has a button you need to push to activate the bluetooth whenever you need it, but I don’t think I will ever need it. And I didn’t want to cut any holes in the case. I have a heavy duty shunt battery monitor that tells me all I need to know. I am a bit of a novice, so I don’t really know that all those readings would tell me anyway.So, I took the two batteries up to my off-grid cabin and connected them in parallel. Everything is working great! But now I have a new problem, I need more solar panels. I have three 100 watt panels, I had set up when I was only running two 100 ah AGM batteries. Now with 500 AH, the solar panels can’t keep up. But that is a good problem to have. But with my small cabin and fully-charged batteries, I could go about 10 days without any sun. I only use it on the weekends, so I think I am set for a while.

Works perfect on our boat. Connected to a 12 volts 608 ah eve lifepo4 bank.No active balancing. (Option)

Doesn’t balance batteries, won’t let you configure to balance them. This unit is trash and customer service won’t help me. Number listed on the site is disconnected and chat support never responds

Although these are very professional, bms’s they’re not perfect. A grade a battery is what all good bms’s want to work with they going up and down because they matched. Grade B batteries aren’t has harmonious, going up and down and the BMS works its ass off. trying to keep them balanced they may be brand new batteries to you B batteries are just hard to work with. They had the most problem reaching the highest voltage and capacity because they’re turning on and turning off one or more batteries is an overachiever, and the rest are underachievers and the same is true when the discharging so the BMS shuts off and let the rest of the batteries catch up and the other slow down . Grade B battery set can be used, but by no means ever going to achieve what a grade a battery can do.. your batteries are taking a long time to charge and you blame it on the BMS. Check the voltage on the rest of the batteries and compare and you’ll see which batteries are the bad ones or should I say not as good as the rest. When you pay for what you get start with the batteries and don’t blame the rest on the BMS thank you. If your BMS doesn’t activate yet, everything’s hooked up correctly short the black wire of the BMS to the blue wire and it will activate the BMS if you have a temperature wire, make sure it’s plugged in because if not, the BMS will not work I usually do 12 V 200 amp power batteries, and run a coffee pot, and that’s 1800 W which have absolutely no problem

I've always seen Daly BMS's used throughout the DIY community, so I ordered this for my first large project. Initially, the BMS would not wake up and allow charge and discharge. I jumped the gun and returned the item before talking with the seller. They contacted me after receiving the return product notification and we discussed my problem. While I was not able to intercept the original part, they sent me a replacement unit anyway and walked me through the setup. Turns out, there is a very small button on the Bluetooth dongle that you have to push to wake the module up. It wasn't pointed out in their printed instructions that came with the BMS, but that did the trick and the unit works well. Downloaded the Smart BMS app and was able to easily find and pair the BMS to my phone. App has tons of configurable parameters like battery bank size, acceptable cell voltage Delta, high cutoff cell, low cutoff cell, high cutoff pack, low cutoff pack, temperature, etc. Very happy with performance so far. BMS is built like a tank and should have no problem pushing full load current.

This thing is far more robust than I anticipated. The app is kinda trash, though.

It works

This BMS is sorta good I guess for protecting the battery from over charging. Although I have seen the BMS hit set limits and not shut things down. So either the BMS is not doing its job or the Bluetooth app is not accurate. The balancing is worthless if your cells get to far out of balance. For the money I would look elsewhere.