Questions tagged [bms]
A battery management system (BMS) is any electronic system that manages a rechargeable battery (cell or battery pack)
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SMBus interface between BQ40z80 communication with STM32 MCU
I’m working with an STM32L452RE Nucleo board and a BQ40Z80 EVM, and I’d like to set up SMBus communication to control the BQ40Z80 using the MCU. Specifically, I need guidance on Checking if the ...
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BMS 3S (S-8254A) with SJT-150E charger won't fully charge
Lately, i've been trying to use a BMS 3S that is based on the S-8254A IC to charge a group of three cells that I planned on using in series.
To charge the cells , I'm using a 12,6V 10A SJT-150E. This ...
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Need 72h of autonomy lithium battery pack for 5V devices
I'm working on a new project that requires power for:
Raspberry Pi 4 (15W = 5v, 3A)
2 fans (0.5 W, 5v, 0.1A)
one video camera (5W = 5v , 1A)
That's in total ~20W. Notice that it seems that the RB4 ...
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Confused about this BMS
I recently got a BMS model "bw-6022-5s" and planned to use it with my 4S5P (21V) battery pack. However, since this BMS looked different from the ones I'm used to, I did some research and ...
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Need recommendations on my PCB
I’m designing my first 4-layer PCB for a 2-cell battery monitoring system using the BQ40Z50 BMS chip.
According to the datasheet, it’s recommended to create two separate grounds: one for the fuel ...
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MOSFET Breakdown Voltage for this BMS circuit
I'm trying to design a BMS which has the following characteristics:
20 lithium-ion cells
in the discharging state, the cells are connected in series to develop a voltage of 84V max
in the charging ...
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Connect BMS to a battery pack of three 18650 cells connected in parallel
I’ve assembled a battery pack using three 18650 cells connected in parallel to power a circuit that requires 3.7V but with extended battery life.
I wanted to ensure the cells are protected, especially ...
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Using a 12 V DC charger and 8.4 V BMS circuit to power a 5 V load
Link to my original question, which led me to this current question after implementing feedback that I received there.
Charging a BMS and providing power at different voltages
It's clear to me that I ...
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Charging a BMS and providing power at different voltages
I've designed a BMS based on the HX-2S-JH20. The BMS design itself is clear to me, but as I want to use a 12 V DC plug for charging. The BMS takes 8.3..9 V, the circuit takes 5 V. I wasn't quite sure ...
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What kind of connector should I use for a 13-pin BMS?
I'm trying to design a 13s 5p battery pack for an e-bike and am not sure about what types of connectors would be most appropriate between the BMS board and the battery for the sense + balance wires. I ...
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connection bms 1s and tp4056 together
i'm noob with the circuits and diy in general. I'm asking this question here after a lot of searches between Google and YouTube on the subject. I'm trying to use a parallel of 2 18650 lithium ions to ...
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Do typical LiFePO4 BMSes react to voltage drop properly in case of charging high voltage cutoff?
Typical LiFePO4 BMSes have several protections:
Temperature protection (low, high)
High current / short circuit protection
Low voltage protection during discharge
High voltage protection during ...
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Is this the correct way to wire up a 5v circuit with battery backup?
Guilty of watching many bad youtube videos on how to set up a battery pack. I've come across many posts that talk about why some setups are wrong, but haven't come across a diagram or video that ...
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Is it possible to get a dual supply from 2S Li-ion battery which has a battery protection IC connected to it
In the image below, can the node connecting cell 1 and cell 2 be used as ground and PB+ as the positive rail and PB- as the negative rail? Those positive and the negative rails will then be regulated ...
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The role of Q33 and the connection of pre-discharge circuit in the BMS circuit
I'm trying to understand the following circuit which is taken from the TI's TIDA-010216:
I don't understand the role of Q19, D29, D30 and Q33 in the circuit. According to this post, it seems that Q19,...
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Connecting multiple Li-Pos, each with a separate BMS
I have some 3.7v Li-Po batteries, each has a welded BMS, and they're all the same capacity.
I need to connect them to get 11.1V and also be able to charge it.
Would that be possible, or the BMS will ...
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Common Ground Issue for the System
I am facing an issue with my common ground for my system.
The system below has a voltage of the battery equal to 16 V and the power supply is supplying my MCU with 3.3V and 0.20A.
What is the ...
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Simple circuit to charge and balance 7.4v li-ion battery (2s) 2x 3.7v cells in series
I am looking for a simple circuit to charge and balance 7.4v li-ion battery (2s) 2x 3.7v batteries in series, and also with over-charging, discharging, current protection
I have found many circuits ...
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BMS-Battery System
I am facing an issue, I am building my circuit found below in the image, I am managing a battery pack using a BMS (link: https://eu.mouser.com/datasheet/2/389/STM_4_19_2023_DB4989rev1b-3159205.pdf) (...
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Selecting the generator frequency for an active battery balancer
I started researching ways to balance batteries and settled on capacitive balancers. I found a diagram on them and most of them use NE555 to generate a square wave with a frequency of ~7 kHz and a ...
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Creating a 12.6 V 3S Lithium-ion Charging Circuit from 5 V USB-C
I have some questions about what is considered standard for a charging circuit, as this is something I have not much experience in. I am constrained to the following:
3S lithium-ion battery of 2600 ...
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Can PE and GND be the same for HY2112 to Function?
If C1 is connected to GND instead of PE, will the HY2112 device fail to disconnect the battery?
My understanding is that HY2112 (similar to DW01A) measures cell current using R2 as a shunt. If OC for ...
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How to drive P-Channel MOSFET For Highvolatge Precharge Ciruit in BMS Application
I am designing a BMS for 24S NMC (100.8 V) and looking for perfect solution for precharge on high side. I designed this circuit. It would be awesome if you folks comment on this and please let me know ...
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18 V AC to 5 V DC circuit design with battery
I’ll start by saying I have little understanding of electronic circuits. I have an old door phone to which I have connected a wireless switch in order to be able to open my door with a remote control. ...
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Analysing 42v to 3.3v DC converter circuit & component identification
I'm analysing a circuit responsible for generating 3.3v for a stm32f103c8t6 on a battery management system(10s). Its a completely proprietary battery management system with nothing online about it so ...
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Are the data pins necessary on a mini USB connector used only for charging a tablet? Is the ID pin used for OTG?
I have an older tablet, and I plan to replace the charging-only micro USB connector (which does not transmit data) with a USB-C connector. However, upon examining the pinout, I noticed that the two ...
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What type of device is this on TP5000 Application Exapmle?
Data Sheet (Chinese)
Question 1
Component N1 looks similar to a mosfet but doesn't look like other ones that I have seen for N-Channel. What is this component supposed to be? This example is for LFP ...
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Powering a microcontroller with an Li-ion Battery --> How to choose a protection?
The introduction
I'm currently working on a low power project that is using the ESP32-S3 microcontroller variant from Seeed Studio, the XIAO Series ESP32-S3 (Official wiki: https://wiki.seeedstudio....
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Can I charge my 3S2P 18650 battery (12.6v) with a normal 12v power adapter if I use a BMS with built-in balancing+protection? [closed]
First off, I would like to stress the fact that I am no electrical engineer or anything of the sort, just a hobbyist that is into this kind of stuff. So please bear with me, as I know a few things ...
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How best to charge a 120 V series assembled Li-po?
I purchased ten 12 V, 30 Ah batteries to be run in series up to 120 V. The problem is that they each come with a 12 V, 3 A internal BMS.
I assume I must disconnect their internal BMS as the combined ...
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Bipolar 2s1p Li-ion array BMS and charging
For powering my portable circuit, I need a bipolar power supply of ±2.5 V. The circuit is low-power, but requires very precise power.
For its stabilization, I am using ADM7154 regulators for positive ...
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When to include a fuse in a battery protection circuit?
I am working with the MAX17320 and I am looking at two MAX17320 example circuits from AD - the MAX17320 Eval Board and the MAXREFDES1299 for inspiration. Each schematic is roughly the same, except the ...
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Can I make my Battery Pack Much Efficient in my DIY Power Bank?
I was having a project of a DIY power bank as a backup for my phone. I need to use super thin batteries for this application. my goal is to make this power bank as efficient as possible. now I want to ...
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Electrically Changing Battery Pack's Setup
I was planning to make a small power bank that has a 6650mAh Battery capasity which has 7 950mAh Batteries. now my plan is to use it to discharge using a single battery and charge the other batteries ...
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Vax Blade 4 BMS board issue (5 x 21700 cells Li-ion 18v battery)
I have a problem with our VAX blade 4 4.0ah battery. Referencing this page: Repairing a 5-cell Li-ion battery: dead 21700 cells replaced, but BMS still reporting error when charging it seems that a ...
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Reduce the current from a Li-ion battery with 6S 18650 cells and BMS to a motor [closed]
Beginner in electronics looking for advice. I got a 6S BMS board from AliExpress rated at 25 A. I need to reduce current to 5-6 A. The board goes in a mobile vacuum cleaner, its motor is max. 120 W.
I ...
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What is this shorted diode from a Bosch BMS for an eBike?
I am currently trying to repair a Bosch BMS from an ebike and found a shorted diode so far.
I can't figure out what exact model the diode is can anybody help me to identify it?
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Can a 4.2V cell BMS function with 3.6V cell?
I'm trying to make a Li-Ion battery with a BMS (Battery Management System). All BMS I found were for 4.2V cells, so my question is, can I use it for a 3.6V cells?
Note: These are LiIon cells, NOT ...
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BMS 3S 25A circuit diagram explanation [duplicate]
Can somebody help me figure out what the circuit in the red box does?
What is the purpose of the six FETs and how do they behave once P- is connected to the negative supply voltage?
What is the ...
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6-pin SMD identification on BMS smart controller
Can anyone help me identify the component in the attached picture? I've never seen a similar package.
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Balancing Circuit for 2S Battery Using MAX77958 and MAX77960
I am currently working on designing a battery-powered device and have decided to use the MAX77958 and MAX77960 for the battery management system (BMS). While reviewing the datasheets and the ...
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Simulink - too much current is drawing from batteries
I am trying to simulate an active cell balancing circuit shown in the figure. However I have some problems. If I only turn on and of the switches I get normal,calculated current passing through ...
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Using two "tool batteries" in parallel - Need a BMS?
I have built a Bluetooth speaker, which is currently powered by a single 18V "drill battery" (Bosch BAT609 battery, to be exact - each pack has 5 lithium ion cells, and I assume, its own BMS ...
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4P 3.7V 32650 Rechargeable Battery 8200mAh needs 1 , 4 BMS or none?
I intend to put 4 X 3.7V 32650 Rechargeable Battery 8200mAh in parallel to keep 3.7V but increase the amperage so the battery last longer.
Looking around is very confusing if for paralel I need or no ...
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Protector and Charger Circuit for 2P2S 18650 Battery Pack
This post is in addition to my previous post of a different design I was exploring.
I am trying to design a custom circuit akin to a BMS that allows for the charging of 2P2S battery pack whilst also ...
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Designing a BMS for 2S2P 18650 batteries
I am trying to design a BMS for 4 18650 batteries in a 2S 2P configuration.
Some of the requirements are:
I would like to charge and discharge from the same connectors
I would like to implement a ...
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LiFePo4 Battery's BMS is clipping when my relay switch kicks-in
simulate this circuit – Schematic created using CircuitLab
My trolling motor had no "kill-switch" that would turn the motor off should I get dumped into the water. So I purchased a ...
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Designing a Li-ion charge-discharge controller circuit
I have an interview test task to design a device that contains several sensors of different purpose and a heater.
The problem is that the device has to be portable, so I calculated the required Li-ion ...
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TL431 With LM317 BMS
I am trying to make a BMS circuit that I saw online using a TL431, but as I am new to electronics I am having some problems when using the TL431.
When I wanted to check the reference pin of the TL431,...
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Choosing Contactors for an EV Battery Pack
I’m designing a battery pack and am uncertain about which contactor to select. Many electric vehicles (EVs) use three contactors: one each in the positive terminal, negative terminal, and precharge ...
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