Questions tagged [batteries]
An electric battery is a device consisting of one or more electrochemical cells that convert stored chemical energy into electrical energy.
6,083
questions
0
votes
0
answers
24
views
How does this charge controller work? [closed]
I just bought this PWM charge controller (https://www.bimblesolar.com/offgrid/chargers/5a-pwm-waterproof-v2) to go with my solar panel as I was planning to use it to charge some batteries.
I have a ...
- 13
0
votes
0
answers
41
views
Battery Charger - Design of Circuit
Im Designing a Lead-Acid Battery charger, dont't needed that this charger it's the most sophisticated one.
As you can see in the attached image, It only consist of a power transformer, a ...
0
votes
0
answers
21
views
How do I calculate or estimate how long a battery operated circuit will power an audio exciter?
I understand that this question has a lot of moving parts to it and I am quite a noob.
I have a battery operated circuit which in turn powers a planar audio exciter (such as this one: https://www....
- 11
0
votes
0
answers
34
views
How is power taken drawn from a home battery/inverter in preference to mains/grid power [closed]
I have a home battery energy storage system with some solar panels, the solar panels don't provide enough energy for me to be completely off grid (especially as I'm in the UK where the weather is ...
- 101
0
votes
0
answers
28
views
Can we charge a 12S LiPO battery through a DC safety switch?
I'm working on a robot that uses a 12S battery as its main power source. The problem is that wanted to add a short circuit protection and an overcurrent protection, so added a DC automatic safety ...
- 411
-1
votes
0
answers
35
views
design of a 12v dc hot plate using a solar powered battery [closed]
What are the components(material) needed and what factors can someone consider when designing it?
0
votes
0
answers
31
views
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?
- 291
1
vote
0
answers
49
views
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 ...
- 291
-1
votes
1
answer
61
views
I am asking that Can anyone tell me which mosfets to use for for charging Circuits using bq24133rgyt , also explain the working if possible , also I [closed]
Can anyone explain me the charging circuit using ic bq24133rgyt, and also provide with mosfets datasheets used in that circuit,
`
- 11
0
votes
1
answer
49
views
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 ...
0
votes
0
answers
47
views
Making a flashlight watch
My son has a rare genetic disorder (nyctalopia) in which the rods in his eyes don't work and so he can't see anything in dim light. I've seen him very confused and scared in environments where I can ...
- 427
0
votes
2
answers
95
views
Best battery type for outdoor equipment
As per the title, I'm looking for a battery that can be left outdoors (in an enclosure) and withstand a wide range of temperatures, from around -5 to 40/45 °C.
It will be kept under charge constantly ...
- 13
0
votes
1
answer
59
views
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 ...
1
vote
1
answer
142
views
Using a potentiometer to adjust a capacitor voltage
Update:
The purpose of the circuit is to cause a capacitor's voltage to be set to the voltage on the wiper of a potentiometer that is connected from battery to ground.
I.e. when the potentiometer is ...
1
vote
2
answers
68
views
Battery (Charge-/Discharge) Efficiency Curve
I’m working on an university assignment at the moment and can't figure out how to do derive the efficiency curve of my battery.
I have a fully functional battery model (on current/voltage level) on ...
- 11
0
votes
0
answers
32
views
Mainboard heated/reballed components - mobile phone [closed]
I recently attempted a DIY repair on my Samsung A51. I heated the motherboard in an oven, suspecting that the solder joints on the board might have been disconnected. Additionally, I replaced the PCB ...
0
votes
2
answers
59
views
In a DC circuit with a battery and a capacitor how do electrons on the capacitor plate connected to positve terminal flow?
In a DC circuit with a battery and a capacitor how do electrons on the capacitor plate connected to positive terminal flow? It seems the voltage between them and the positive terminal of the battery ...
- 15
2
votes
1
answer
51
views
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 ...
- 23
0
votes
1
answer
29
views
Why does loading a circuit cause voltage drop in DVOM?
So this question relates to cars but applies to all electronic circuits really.
I was watching a car diagnostic video on youtube and in the video he demonstrates the difference between doing voltage ...
- 27
1
vote
2
answers
67
views
Why don't oppositely charged ends of separate batteries and capacitors produce current flow? [duplicate]
I have a question here regarding the flow of current from charges.
I understand if you connect a simple circuit to a battery it creates surface charges which allow the current to flow.
My questions ...
- 63
1
vote
0
answers
18
views
Does "Torque control" using FOC consider input (battery) voltage drop?
All information related to Torque Control using FOC technique consider a current control, so they suppose a correlation between req_Id (Id desired) and requested mechanical torque. PI regulators ...
19
votes
3
answers
4k
views
Can this battery be charged?
I have a battery that looks like a lead acid battery, contains lead, and it's from one of those little electric cars that kids can ride on, so it should be chargeable, but it says on the casing not to ...
- 27.1k
0
votes
1
answer
39
views
Drone power distribution board for multiple battery setup
I'd like to add multiple Li-po batteries to my octocopter without worrying about different voltages across different batteries while also allowing regenerative braking.
I have seen designs where ...
- 1
0
votes
3
answers
90
views
How is a DC battery’s voltage distributed across the components in an ideal wire?
If the sum of voltage drops in a circuit is equal to the battery's voltage, then how do the electrons maintain their flow after passing the voltage-dropping components if the components had already ...
- 15
1
vote
1
answer
31
views
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 ...
1
vote
1
answer
50
views
Best approach to switch high-power charging port
I have a robot with a high-capacity 24V Lithium Ion battery, that is going to be charged with a 70A charger.
The robot is supposed to be able to toggle charging on/off through an input signal.
...
- 13
2
votes
2
answers
83
views
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 ...
- 21
0
votes
0
answers
40
views
3.7 V Li-ion rechargeable battery
I have a rechargeable flashlight that uses 3 Li-ion 3.7 V batteries. This flashlight works great the light is extremely bright and adjustable. It's one of those flashlights that plug right into the ...
- 1
0
votes
0
answers
22
views
Charging a super cap with a Li-po battery while maintaining charge
I have a 3 V 100 F capacitor and 400 mAh 35 C battery, the battery is to be charging the super capacitor and maintaining charge until a button is pressed to discharge the super cap. I am stuck with ...
- 199
2
votes
0
answers
43
views
Design a 12 V battery pack for portable electronics project [closed]
I am doing some electronic project for a portable escape room business that I am running with my wife, the project are basically running or Arduino to take some inputs and switch on a 12 V solenoid ...
0
votes
1
answer
61
views
BJT voltage rail
I have run into some misunderstandings regarding voltage rails in circuits with components such as BJTs. And not the BJTs, but rather the conventional current model schematic made, and the real thing, ...
- 75
3
votes
1
answer
52
views
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 ...
2
votes
3
answers
113
views
Powering a 3 V motor with 2xAA batteries for several hours
I have a 3 V toy motor that I want to run with some kind of stability using 2x AA batteries. In terms of load, imagine a little fan. I'm not sure how much torque that would add.
The motor is a brushed ...
- 21
0
votes
1
answer
56
views
Regulating 4 AA batteries to 5V over the discharge cycle of the batteries?
Over the discharge lifetime of these batteries the voltage might range from 6V down to 4V.
If the batteries were consistently over/under 5V, I could use a step up/step down converter such as a MCP1640/...
- 10.5k
0
votes
0
answers
49
views
DIY motor project - Help needed for configuring Maytech 6374 motor
I have very elementary electrical knowledge. I need help with configuring motors. I have dual Maytech 6374 motors (150 kV, 08 A idle current, 65 A max current, 60 A rated current, max output 3550 W, ...
1
vote
3
answers
88
views
Unable to start and run 12 V DC pump, only jolts
I have a 12V 19 watt DC water pump (800LPH), A 12 V DC step down converter, and two Dewalt batteries.
One at 18 V 5 Ah, other 18-54 V 9 Ah.
I've connected pump to step down to battery correctly, but ...
- 23
0
votes
1
answer
72
views
How to power ESP-12 (ESP8266) with LiFePO4 battery?
I've tried several different programs. A simple blinking program results in nothing. It works when connected into the programmer:
The ESP12 has a blue LED. The LED blinks only when connected to the ...
- 616
1
vote
2
answers
47
views
Battery voltage dropping without load: what does this say about its health?
I have three AGM batteries (VARTA LA95, 12V, 95Ah) that I want to connect in parallel in a battery bank.
They were connected to a Victron charger for a long time and now that I turned it off, I began ...
0
votes
3
answers
75
views
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 ...
- 203
0
votes
0
answers
34
views
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 ...
- 1
3
votes
1
answer
93
views
Charging car battery with another car - circuit schematic
I came across an example in a textbook that talked about charging a dead car battery with another car battery. They provided this picture of how to connect the two batteries: -
Source: Engineering ...
- 3,656
1
vote
2
answers
64
views
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 ...
- 11
2
votes
1
answer
32
views
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 ...
1
vote
1
answer
90
views
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, ...
- 11
0
votes
0
answers
23
views
2 BMS in Parallel connected to 2 batteries in series
This circuit is for charging the two batteries only. The LED board will run on 3.7 volts, but 7-8 volts does not affect the function of the LED board. With this circuit, the LEDs will stay bright ...
1
vote
1
answer
40
views
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 ...
0
votes
1
answer
28
views
DfPlayer Mini not working when using three LR44 batteries
I'm working on a small project that plays audio. This project uses an ATtiny85 and a DFPlayer Mini as well as some other small components to make the whole thing work. I've tested the circuit using an ...
- 59
1
vote
1
answer
19
views
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 ...
- 23
2
votes
2
answers
36
views
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 ...
- 21
2
votes
2
answers
55
views
Can you reliably use the voltage of an empty battery in a circuit?
I am making my first battery powered circuit. I am confused as to what happens when a battery is getting close to empty. Here is a quick example of what I am confused about:
From my understanding a 12 ...
- 1,032