Questions tagged [lithium-ion]
Questions regarding Li-ion (lithium-ion) cells and batteries, including proper charging and usage.
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Can LiFePo4 batteries be charged using an SMPS with adjustable voltage output?
Some Switched Mode Power Supplies offer a potentiometer to adjust their output DC voltage. Mean well's [LRS-350-24] power supply for instance has an adjustable range of 21.6 ~ 28.8V. Can it be used to ...
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Low Power Lithium-ion Charge Protection
I have ~100 mAh 6 V solar cell that I want to use to charge 18650 lithium-ion battery.
Purpose is to use a PIR sensor to turn on light when someone passes by,
I am not very confident about the ...
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My home-made Li-ion protection circuit oscillates
Now that I have this circuit up and running a new problem rose up:
When I go down to 3.2 V the MOSFET shuts down as intended but the when I go up with the voltage the output oscillates and draws ~0....
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Li-ion undervoltage lockout
I wanted to add to my power supply circuit an undervoltage lockout based on this but with different components. The circuit looks like this:
simulate this circuit – Schematic created using ...
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21700 Lithium Ion Cell Battery Packs [closed]
I'm struggling to find commercial (not custom), certified (UN, UL), low-profile 21700 lithium ion cell battery packs.
Are they elusive or non-existent?
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21700 Lithium Ion Cell Battery Packs : Commercial, Off-The-Shelf, Direct Purchase [closed]
Background
I am attempting to design a 3Sx2P or 2Sx3P cell-array of lithium ion 21700 high-capacity (3.7 [V.nom], 5[Ah], ≤10 [A.nom]) cells to embed in a low-profile portable electronics system.
(I ...
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Battery Bank Replacement [closed]
I have an old power bank with swollen battery with the specs you can see in image 1
This is the module, but I can't find any specs nor schematics on the internet.
The image below will show the full ...
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Lithium ion BMS bypass (or hack) [closed]
I'm trying to turn a scavenged scooter battery into an e-bike one.
I can balance charge it via the original BMS but discharging is the issue: P+ and P- are only delivering about 4 V.
More wires, with ...
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Li-Ion BMS Feature Overlap: Charger, Cell Balance + Monitor, Protection, Fuel Gauge [closed]
Background
TI has a suite of battery management ICs for:
Charger
Cell Balance + Monitor
Protection
Fuel Gauge
While the chargers tended to be their own thing, many of the ICs had feature overlap:
...
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Isolated two battery load/charging system (parallel 18650)
I am working on a project and wanted it to be very robust and user-friendly. To power said device, I had planned on using two 18650 in series (li-ion), like everyone else. The problem I had was that ...
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Li-Ion BMS which protects parallel cells in addition to series cells
Background
If li-ion cells are arrayed (series x parallel — S x P or P x S) to form a battery, it is generally recommended to manage parallel stacks of series cells (P x S) independently, such that ...
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NTC wire in a replacement LI-ion battery has a different color [closed]
I am replacing a battery pack in a speaker. It is a Li-ion 18650 2600 mAh 7.4 V. I got a replacement from a shop in China claiming to be local. The replacement has an NTC and three wires just as the ...
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Problems trying to monitor two 3S Li-ion batteries from an Arduino, while powering that Arduino
So what I'm doing might be actually a little haywire, but here goes:
I'm using an Arduino to power a series of relays that control some 24 volt valves. The power source is two Milwaukee M12 batteries ...
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Difference in Li-ion battery safety management for RC models compared to other applications
As generally known Li-ion batteries (whether pouch or cylindrical) may catch fire but depending on the application I see completely different attitudes of the users:
Consider as one group RC car ...
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How can I handle regenerative braking when the lithium-ion battery is full?
Long version
We are using third party motor driver with regenerative braking and a lithium-ion battery. Apparently, this combination is well known in e-bike enthusiasts world as having a huge problem ...
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Two 14S Lithium-Ion batteries have different charging speeds: the smallest is slower than the higher capacity one
Long story short: I built one 14S battery last year, using Molicell P42A cells. 6 cells in parallel for every series. So, around 58.8V total voltage on the battery.
Recently I made another battery ...
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Which specific type of P-MOSFET is suitable for Reverse Polarity protection for 18650 li-ion battery circuit?
I'd like to make a reverse polarity protection circuit for 18650 3,7V Li-ion battery (like here: Can I use a p channel mosfet as reverse polarity protection but still charge a Li-Ion battery?)
I only ...
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Criteria to see if a battery was over-discharged in the case of Li-ion cells and NiMH batteries
Consider a Li-ion pouch battery from an RC model. Is there any reliable way to determine by measurement if the battery was in a over-discharged state in the past. (In particular I am looking for ...
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Li-ion cell voltage drops over time while charged from a MCP73831 IC and while USB powers the load
I’m using the diode pair solution from @james in this post with a MCP73831 and a 2000 mAh Li-ion pouch cell with this basic charging circuit:
And then one SS14 diode from Vin to the input of this 5 V ...
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What thermistor for a TP4056 lithium charge module?
This TP4056 Li-Ion battery charger datasheet specifies an NTC thermistor be used for battery temperature sensing while charging. Is there any further specification I should know about the NTC ...
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Charging two 18650 cells connected in series?
It is easy to charge a single cell or cells connected in parallel with a single TP4056 module.
This question shows why this can't be done with cells connected in series (short circuit of the cells).
...
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Reason for P-MOSFET between the charge N- FET and charge pin of bq76930
I am currently working on a final year project which is a device like a power-bank, but this will be able to charge both phones and laptops.
After a lot reading and research I finally considered using ...
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Protecting parallel 18650 cells
My son is doing an Eagle project where he is creating a solar charged LED light set up using two 18650 cells in parallel. We are working to ensure they are safely protected. From the research we have ...
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How to charge a battery pack through BMS using same pins as for the BMS output
I'm bulding a 18650 4S pack for a speaker and I'm using a BMS capable of balancing and protecting the batteries like on the picture below. The manufacturer advertizes you can both charge and discharge ...
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Powering 150W 24V DC motor
I have two very basic motors, basically this one: amazon
Motor specifications:
Power: 150W
Volts: 12-24V
Amps: 4.42 @ 12V, 4.76 @ 24V
Speed: 3300 RPM @ 12V, 5500 RPM @ 24V
The project is a robot ...
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Lithium battery pack in series or parallel
The goal is to build a 200V Lithium battery pack using 21700 cells.
I am trying to make a design decision on lithium battery pack architecture for an electric vehicle and it boiled down to below two ...
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Designing a Power Supply for a 24V 350W Motor Using 18V Tool Batteries: How to Safely Parallel Them?
I'm currently working on a project where I need to design a device to power a 24 V, 350 W motor using 18 V tool batteries. The 18 V output from a single battery is sufficient in terms of voltage, but ...
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Choosing correct BMS for 12V lithium battery pack with 39 cells
I have 39 lithium cells, I want to make a 12 V battery pack with as much AH as possible. From what I've read, all BMS are only for cells connected in series. So for example, all 12 V battery packs are ...
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2S Li-ion charger+protection with reverse protection
I'm designing a device powered by two Li-ions in series and I'm struggling with the charging and protection of the batteries. One of the requirements is to avoid battery packs, the individual cells ...
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Lithium Ion Battery : Cell Array Configuration (V.batt when converting to ≤ 4[V] )
Question
I am seeking to array 6x 21700 lithium ion battery cells, leaving the option for:
1S • 6P (@ V.batt.nom = 03.7 [V], range: 02.7—04.2 [V])
2S • 3P (@ V.batt.nom = 07.4 [V], range: 05.4—08.4 [...
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12 V 20000 mAh Li-ion battery pack gets very hot
I'm trying to power a heated lunch box I got from Amazon (this one) via this - 12 V 20000 mAh Li-ion battery pack, which appears to be 6x 18650s.
When I plug it in, the battery heats up significantly, ...
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Using 2-cell lead-acid battery as direct replacement for single-cell lithium-ion battery
I've designed a system that remotely logs some data (position, some weather data, etc.) in remote areas that currently uses a single lithium-ion battery (~850mAh) that is recharged via a solar panel ...
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Can Li-Ion BMSs be used with LiPo batteries?
I'm building a robot that's running on a 12S, 10400 MAh LiPo. Because of obvious reasons, the system requires a protection circuit. My question is, can I purchase this 13S (which I suppose works with ...
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Can I use a MAX17262 to measure battery capacity of a 300mA 3.7V Lipo?
First, I a very basic understanding of lithium based batteries and from what I have learned, gauging their capacity can be quite complex. I was looking into MAX17262 as a fuel gauge to measure the ...
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Supplying 4 V (max 3 A) to my circuit using lithium-ion batteries
I'm designing a circuit for a portable device, and the main component requires 4 V (±5%) up to 3 A (12 W). The 3 A is the max for the circuit- typical load is 250 mA.
As I understand, the voltage ...
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What to look for when selecting a lithium ion battery charger IC
I'm looking into battery charging ICs for a 3.7V Lithium Ion battery, and want to make sure I understand the criteria involved in searching for such an IC.
The obvious one is to make sure the IC is ...
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When I test a 18650 Li-ion cell, why do I get two different values of capacity for charging and discharging?
I'm trying to test the capacity of 18650 cells. I don't know which numbers are important. I get different results on the same cells from discharge and the charge.
For example on same 18650 cell:
(...
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How to prolong a lithium battery life mathematically?
How to use a lithium battery so that it gives as much energy as possible in total during all battery discharge events from the moment of purchase until the moment when its performance drops to some ...
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Can I "Stack" 2-Cell Li-ion Battery Balancers for a 4-Cell battery?
I'm building a project where I need an internal rechargeable battery. I've decided to go with 4x 18650 Li-ion cells, so I can change them if necessary, the 4x 18650'ies will be used in series, for a ...
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On/Off switch for Li-ion battery pack
Is it ok to tie the battery pack (in my case 3s1p) to a SPST switch to turn it on/off or I should need a series resistor after the switch to limit current and a big fat cap to smooth the on/off ...
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Replacing 8 AA batteries with 3 186500 batteries
My old R/C toy car, can be powered with 8 1.5V AA batteries or 8 1.2V Ni-Cad Batteries. Currently I try to use 3 186500 Li-Ion batteries instead. I planned to use a charger- and protection module ...
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Stray Capacitance in a Lithium-ion battery pack casing
I made a Lithium Ion battery pack for a diy car project using cylindrical cells and observed something interesting. First, I'll lay out the pack details:
Configuration: 1p96s
Max Voltage: 403.2V
...
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Cell vs battery discharge curve
I have a battery pack composed of 16 cells in series.
(Battery pack link: https://www.innopower.de/produkt/innopower-lfp-105ah-eve-battery-pack/
Cell link: https://www.innopower.de/produkt/innopower-...
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Safer alternatives to Li-ion battery packs while experimentation/development
I am developing a quadcopter from scratch (mainly the flight controller part) and at times I need to connect the whole system to a power supply that can sustain high currents for testing. I have the ...
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DS3231 module li-ion charging circuit tweak
Most of the DS3231 modules come with a "charging" circuit for a LIR2032 battery. I understand that, as-is, it's considered garbage.
The reason people say not to use the module as-is is due ...
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Why won't my LT3652 circuit charge my Li-Ion battery pack?
This is a revision of a post from a few days ago. I'm currently working on designing a solar charge controller using the LT3652 chip that takes a solar panel input, charges a battery pack, and also ...
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How to add 2 or 3 parallel Li-ion cells to my custom PCB
I've tinkered with electronics and components for quite some time now, but I'm kind of a noob when it comes to taking things to "production".
I've this project using an ESP12-E, powered by 2 ...
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Charge my DIY 18650 battery pack with DW01A BMS board
I am currently in the process of making a 3S 18650 battery pack using a BMS board that I purchased from Amazon. The image of the board can be found below:
Yesterday, I successfully connected all the ...
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What kind of model can be used to simulate over- and under voltage in a Li-Battery pack?
So far I have not much experience with modeling in the field of lithium-ion cells or batteries except equivalent circuit models (ecm)-models which I've implemented and used for simulations in Matlab/...
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Advice for my Battery Management/Charging System
I am working on a battery management or charging system for a 3s2p battery topology. It will be used in a project where AC power from an alternator is rectified to DC power and is used to power ...
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