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Battery Management System - What are you using? - How do you like it?
BMV712 is what I use. Love the Bluetooth option with the app. I installed in the rv baseman it 3 years ago and haven’t looked at the display ever since.
2018 RAM 3500 Big Horn, CC SB 6.7 Cummins HO/Aisin
2021 GD Imagine 2800BH
BMV712 is what I use. Love the Bluetooth option with the app. I installed in the rv baseman it 3 years ago and haven’t looked at the display ever since.
I didn't realize the BMV712 also took care of management! I thought it was just a monitor. I'm going to have to reconsider trying to just replace my shunt with a smart shunt.
I didn't realize the BMV712 also took care of management! I thought it was just a monitor. I'm going to have to reconsider trying to just replace my shunt with a smart shunt.
You are correct, it is not a BMS. It is strictly a monitor. I misunderstood the question. I have three Battle Born LiFePO4 100AH batteries that have an internal BMS.
Jim
Jim and Ginnie
2024 Solitude 310GK - 2020 F350 Dually
GDRV Technical Forum Moderator
GDRV Rally Support Coordinator
I have Overkill Solar BMS for each of my batteries. I also use the VIctron Lynx Shunt to monitor usage and have an additional temp sensor on one of the batteries connected to the Multiplus/cerbo which helps manage the charge profile for my batteries. IN addition I have 2 programmable relays connected to temp sensors that trigger small computer fans throughout my system that helps air flow when temps get hot.
I am not sure with what you are asking. A battery monitor, like the Victron Smart Shunt, will let you know the state of charge that your battery is at and how much life has been used or left. A battery management system, as mentioned above, is generally installed in a Lithium type battery and manages the battery for over charging, minimum voltage, temperature and maybe others. If you have a Lithium battery it should have its own system built in. If you have the standard lead acid battery I have not heard or seen a battery management system for those, maybe it is out there.
Brian
Brian & Michelle
2018 Reflection 29RS
2022 Chevy 3500HD
The need for a separate, standalone BMS is one of the factors that drove me to Battle Born (who at the time of my purchase was one of the few good battery providers).
Forum moderators are not GD employees--we are volunteers and owners presumably just like yourself. Unless specifically mentioned otherwise, we have nothing to gain should you choose to purchase a product or engage a service we discuss on this forum.
A friend/acquaintance that I met camping in Assategue, that we meet up with every year, built his own system from scratch on a VW bus. I'm realizing he's unaware of the internal BMS because of the batteries he's using. This was his top recommendation, "do this before any other upgrades because the battery is the most expensive and vulnerable part of the system." I'm wondering now if the internal BMS and the stand alone BMS do the same exact thing and if they do should I still use one for redundancy considering they're cheap and my batteries are not.
You are correct, it is not a BMS. It is strictly a monitor. I misunderstood the question. I have three Battle Born LiFePO4 100AH batteries that have an internal BMS.
I have Overkill Solar BMS for each of my batteries. I also use the VIctron Lynx Shunt to monitor usage and have an additional temp sensor on one of the batteries connected to the Multiplus/cerbo which helps manage the charge profile for my batteries. IN addition I have 2 programmable relays connected to temp sensors that trigger small computer fans throughout my system that helps air flow when temps get hot.
Do I win???
Yes Mr. Coleman. You win my request to respond to all my solar related posts!
What kind of batteries are you using. Do they also have internal BMS and you're using the overkill for redundancy?
Bms is part of the lifepo4 battery. Not a stand alone part to buy.
Although you could research batteries by their bms and get the one you like?
Thank you Scott n Wendy. While doing more research after I made this post, I realized that a BMS is part of my battery. You can buy BMS for cells that don't have them built in. I guess that's why I was confused. Here's one...
The need for a separate, standalone BMS is one of the factors that drove me to Battle Born (who at the time of my purchase was one of the few good battery providers).
So it sounds to me like the redundancy of an external BMS is unnecessary in your opinion.
Hortstu -- correct. No need for a separate BMS if the battery comes with an internal BMS IMO. (I've actually never read of anyone doing it--likely to cause more issues than help with protecting the battery bank.)
Forum moderators are not GD employees--we are volunteers and owners presumably just like yourself. Unless specifically mentioned otherwise, we have nothing to gain should you choose to purchase a product or engage a service we discuss on this forum.
Yes Mr. Coleman. You win my request to respond to all my solar related posts!
What kind of batteries are you using. Do they also have internal BMS and you're using the overkill for redundancy?
To save money (and for a fun challenge) I bought some prismatic cells that were already welded in series to create a 24v battery. Below is how they came to me. Note they are just eight 3.2v cells connected (welded) in series. No BMS or outer casing.
If you know about the volatility of lithium battery chemistry, you know a BMS is necessary for safe functioning (read about the Boeing 787 and their lithium issues). So I had to get a BMS for the "batteries".
After much reading, asking and listening to people smarter than me, I decided to use Overkill BMS's. IMO you can't get much better than Overkill.
So I installed the Overkill BMS to my batteries. Based on the available space where these were to be installed, I chose to mount the BMS' to the ends of the batteries (below). The little circuit boards at the ends of the wires of each BMS is the Bluetooth module. I can connect to each BMS (battery) via an app on my phone and configure many parameters.
Each BMS came with 2 temp sensors which I placed on either side of the batteries. These senses are used to monitor temp of batteries which is needed for the over/under temp protection of the BMS.
The Overkill BMS protects the battery/cells in many ways: cell over/under voltage protection (which has been triggered more than one would think during charging), battery over/under voltage protection, charge/discharge over current protection, charge/discharge over/under temp protection.
The BMS also offers hardware (the actual BMS) protection: over/under voltage protection, over current protection and short circuit protection.
I never made an outer casing for them. I used a protective cover, then strapped them onto the floor of my exterior storage space.
I added a "false bottom" over the batteries. It ended up working out well. The space the batteries occupy is not really missed.
So, to answer your question (finally), I only have 1 BMS per battery.
If you purchase a pre-made battery (like Battle Born) they SHOULD have a BMS already connected. IF they do not have a BMS...DO NOT BUY IT. Only purchase a battery with a BMS. Once you buy the battery with a BMS, you do not need to add another BMS. TO do this will not end well...and you would have to tear apart the battery casing to install it.....which will void the warranty in 2 ways....by tearing the case apart and by adding another BMS.
So, my advice, for what it's worth, is that you purchase a good lithium battery from a reliable manufacturer. Those batteries will have a BMS and you will be set without having to mess with the battery at all.
After looking at the link Howard posted, you will need to determine what you want to monitor / control.
If building your own battery from cells then the BMS Jim is talking about is used to ensure cell balancing.
If you have multiple batteries and want to ensure they do not over charge, then Howards controller is the correct one but this means each battery must have it's own controller for the cells.
Unfortunately BMS is more generic than one would hope as each does manage the battery, however, they are completely different animals.
Joseph
Tow Vehicle: 2024 GMC K3500 Denali Ultimate Diesel
Coach: 303RLS Delivered March 5, 2021
South of Houston Texas
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