Electrical Engineering Stack Exchange
Electrical Engineering Stack Exchange

Questions tagged [bms]

A battery management system (BMS) is any electronic system that manages a rechargeable battery (cell or battery pack)

258 questions
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How to deal with ground connection impedance with BQ769x0?

I am working on a battery management system using the TI BQ76920. The document "bq769x0 Family Top 10 Design Considerations (Rev. A)" explains on pages 22f that depending on how ground is referenced, some inputs must be protected from falling below…
ARF
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Battery management system

I am designing a battery management system for lithium ion batteries. I am referring a schematic that is already available. I do not understand the function of the two MOSFETs marked in the schematic.
BlackHawk
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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 a BMS or 4 each battery has one.
Teodor
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10S BMS board with three negative connections: -B, -P and -C

I'm building a 4P10S Li-ion pack and have seen some diagrams that show no connection to -P and others that connect -P to "Discharging negative": What is recommended and why?
Paulo Scheidegger
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Help with 2s BMS charger/discharger board

I have built li-ion battery pack with 2x 18650 cells and 2s BMS board as shown in the picture. When I measure voltage across B- and B+, I’m getting 7.9v, same if I measure voltage across P+ and B-, but I’m getting only 0.1v when I measure voltage…
Anton
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Charger detection in a battery management system

I am working on a prototype BMS using the BQ76940. As per the datasheet, the IC offers only load detect function and does not detect when a charger is plugged in. Is there any alternative to detect the charger? Edit: My BMS is low side configured
BlackHawk
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Undervolt protection circuit

I want to undervolt protect a series of 3 Li-ion cells. The load is a voltage booster with initial 5 amp usage for 5 seconds. Then power consumption is reduced to 5 watts. (It works ok on battery.) (A BMS circuit is not suitable for me.) I want to…
jzeds1491
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Design a BMS (overdischarge protection)

I am tired of BMS that doesn't work the way I want, so I have decided to made my own BMS. Searching on internet I have found the schematic for a 4S BMS and I want to understand how it works before try to create my own 2S, 3S... versions. As I…
Daniel Carrasco Marín
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Choosing A 4s BMS

I am using the panasonic ncr18650pf battery in a 4s pack for my project and I want it incorporate a BMS with balance lead charging. I have already ordered the batteries and holders but I have never built a battery pack so what should the BMS be…
Terrel Ross
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BMS for multi cell batteries

I have several large LG multi-cell batteries. Images & description can be seen here: I'm wondering if I can use a 14S BMS for each of these batteries in order to keep every cell balanced and in check and run them in the series. For example, I want…
PPL_GC
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Is a BMS supposed to be rated at your discharge current or the battery's?

So if I'm making a 13s2p 48v 16Ah battery out of these cells that are rated at 200A each, (3.7v 8Ah), and if I want to power a ~30Amp motor, do I need a 200Amp BMS or a 40amp (40 not 30 because 40 is bigger than the motor discharge current to be…
marsnebulasoup
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