Questions tagged [batteries]
An electric battery is a device consisting of one or more electrochemical cells that convert stored chemical energy into electrical energy.
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Can I mix new and old batteries in a parallel circuit?
I mean non rechargeable alkaline batteries like energizer's, some full, some half empty. I know I cannot do that in series, I forgot why, but what about parallel?
I found answers for rechargeable ...
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Way to calculate the draw limit on a battery
Is there a way to calculate the draw limit on a battery, using any of the Ah, C-Rating, etc. values to solve for the unknown? If so, how do you do it?
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Are there general guidelines for LiPo discharge current?
I'm doing a hobby project where I'm designing a smart RC car around the size of a mini sim card. The BOM has been narrowed down, and I reckon it's doable with a 4-layer board.
Image source: https://...
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Can 3 3.7 volt 6000 mah batteries power two 9 watt bulbs [duplicate]
I wanted to know if 3 3.7 volts 6000 mah hour batteries power 2 9 watt bulbs, and a 12-volt pc case fan? If so for how long?
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Punctured phone battery [closed]
My old phone stopped working. We threw it around and beat it with rocks for 20 minutes until the back came off and revealed the battery. It was all swollen.
We started picking it with a stick until we ...
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Battery Amp-Hours and C-rating (need clarification on formulas)
These formulas here are confusing me. I am not sure, exactly what some of the variables mean.
What is the "Max. Amps" exactly, in this formula?
What is the "discharge.C.value"?
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Wireless charging Lipo batteries
I found this discussion while looking for a way to wirelessly charge my 3S drone battery. I would like to find a way to drop my drone on my desk (like I do my phone) and let it charge.
If I am ...
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Why did my 12v battery charger blow, when connected to a 12v battery in a 48v bank?
this is a puzzler here. I have a 48V bank of Battleborn lifePO4 batteries connected to a huge 10kva inverter.
When I tried to charge one of the 12v batteries while the pack was still connected to the ...
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Damaged Bosch battery charger IC identification help
I accidentally damaged my Bosch cordless drill battery charger by hooking the charger's PCB's 12 volt lines directly to the 220V|50Hz AC mains.
The charger's model is AL 1110 CV https://www.amazon.co....
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Battery with high risk of being exposed to fire
I'm currently working on an electronic design which has a high risk of being exposed to temperatures up to 500°C and possibly more.
The specifications indicate that once the product is exposed to more ...
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What do I need to make a LP-E12 Coupler be powered by either a 18650 or 14500 lition battery?
So I'm working on a Battery Grip for my Canon M50 Camera which uses an LP-E12 Battery which operates on 7.2V. I found a battery coupler for it that has a 7.4V 2A input requirement. I was thinking of ...
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Charging batteries with solar panel
Before I ask my question, I would like to say that im not exactly from the EE field, so please be easy on me.
I would like to use a Solar Panel and ...
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9V SMD "terminals" [closed]
I intend to build my own USB rechargeable 9V battery, kinda like this one.
My main issue with those is that they usually use 2 Li-Ion batteries in series, which produces an insufficient voltage for ...
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Cascading Isolated Power Supply
I want to implement a few chips for battery management and due to the ADCs of each cell working at bigger voltages each, and each chip (I have to cascade three ICs LTC6803-4) with a maximum voltage ...
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How does the continuous/peak charge/discharge current change when combining cells with known values in series / parallel arrangements?
Example
16 identical battery cells rated as below:
3.2V 100Ah
LiFePO4
Max Continuous Discharge 100A / 1C
Max Peak Discharge 200A / 2C for 100s
Max Continuous Charge 50A / 0.5C
Max Peak Charge 100A / ...
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Battery questions
I have some questions regarding making a battery pack for a electric bike. I’m looking at the Samsung 50E 21700 5000mAh 9.8A Battery as the base.
The max discharge current is 9.8A, if I put two of ...
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1.2 V AAA rechargeable batteries, voltage for almost fully charged cell
Some weeks ago, I bought a new pair of AAA rechargeable batteries, NiMH. Its package shows "Panasonic Eneloop" model with up to 800 mAh.
First I connected them in series and connected two ...
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First schematics, DC-DC Converter question
I've made my first PCB design and I am unsure about a few things. This is a H-Bridge with a Attiny85. The Attiny85 will read a analog input on PB4 and adjust the PWM based on that. It is powered by a ...
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Question about mixing battery sizes and quantities
Ok. I have searched everywhere and can't find a definite answer on this:
My first question, Is, Can you mix 2 lithium batteries of different sizes together? (Like mixing an 18650 lithium battery with ...
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UPDATE - How to prevent overheating of my ebike system?
I have a Li-ion battery pack 18650 cells with a BMS, 10 in series by 7 parallel. The pack I bought was defective from day one and had a 7 cell row that got hot when charging now I just repaired the ...
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NiMH battery pack charging circuit using a solar panel
I have been working on a NiMH battery pack (7.2V / 2100mAh) charging circuit powered by a 12V solar panel. With some research I found that charging NiMH takes different forms by measuring change in ...
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How many flash drives can you power with an iPhone battery?
I will give a very specific example:
Hardware:
Iphone X device with 2716 mAH capacity battery, 3.81V
Iphone "dongle" lightning to USB 3.0 port, bus-powered
USB hub 3.0, bus-powered, 3V, 200 ...
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2S 10C Li-po 6000 mAh step-down to 6 V [closed]
There are a ton of buck converters that can step down 7.4 V to 6 V, but looking at their specs, not all of them can handle the typical Li-po high current discharge rate of say 60 A. Is there something ...
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wiring up laser pointer directly to usb power
I have a red cheap laser pointer/lantern which I'm using to do some experiments. But I find that the batteries have a very short lifetime for what I'm doing, It uses three LR44 button cell batteries,
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Do batteries obey Ohm's law during charging?
A Battery can be modelled as an RC network, which has an impedance. If we take 4.2V L-ion battery with internal resistance of 0.1 ohm, and by applying 4.2 V, at OCV of 3.7V, it will not accept 5A.
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Is voltage reduced when load increases? [duplicate]
Would the voltage of a power source decrease if multiple loads / more load is added to it?
I am researching battery types, and wanted to know, if I added enough load to a battery how much / would ...
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Relay for Solar System as Backup Only
Background
I'm working on a seismic alert network and seismograph station at my school in Puerto Rico. We're building a solar system for the system to continue running during a potential seismic event....
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How to find the right battery for my project
I am working on a project that requires 12v 12A of power. But I can't find the right battery. I have been looking at a few online tutorials about choosing batteries but they have not been very helpful....
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12 V load doesn't turn on with boost converter
I'm trying to build a power source for my router during load shedding, but the router doesn't turn on when connected to any sort of boost converter.
I have tried five more different routers from ...
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How many amps between batteries that are wired in parallel?
How many amps will flow through the cables between my batteries if I have 2 batteries wired in parallel?
Let's look at a simple example:
We've got 2 batteries in parallel, and one 12v lamp that ...
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Charging internal laptop battery bypassing board
I own a refurbished tecrq z50a and during a routine clean up i did a mistake of taking off the bottom cover without realizing that it was still shutting down. A screw rolled on the board and sparks ...
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Replacing Nimh battery to Li-ion in hybrid cars
is it a good idea to replace a Nimh battery in hybrid car (like prius model 2012) to Li-ion battery without any problems.
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How do VA and W ratings of UPS supplies compare with mAh ratings for power banks?
I'm trying to figure out how to power a few devices during power outages. I've looked into UPS devices and also portable phone power banks. My biggest problem is how to compare the devices, apples-...
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Modify PCB Mains Voltage input to 12VDC
One of my amplifiers has died so I need to find out if I can hookup a spare I have lying around as per "Section B" of the below block diagram.
I have done the same modification before on ...
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What are the dangers of emulating a battery with a step-up transformer and a 5v power supply?
I take long timelapses, for astrophotography. My camera's batteries are irritatingly short-lifed for this purpose, and so I wanted to try an alternative. I found .stl files for 3d printing the form ...
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Electrical water fountain - what is its power consumption? [closed]
Above is the image of the electrical water fountain given to me by my ex-employer, on account of my birthday. The single LED changes its colour (Red, Green, Blue) every two seconds. It is operated by ...
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Can a voltmeter itself disturb the exact measuring of voltage?
I'm trying to understand the effect on a system when the voltage of the system is measured by connecting a voltmeter.
For example let's say we are trying to measure the voltage of a battery.
To ...
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Is it possible to use adapter as a charger? [closed]
I have a 8V battery and a 5v,600mA output adapter.
so i needed to charge the battery using this adapter,is it possible?
when i connect my battery to adapter, the adapter power led is glow.
is it safe? ...
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How do I prevent my BMS from tripping when solenoid is connected?
I am working on a project that is effectively just a battery powered reticulation system. It is charged through a solar array and cheap MPPT charger, which connects into the battery via the BMS. The ...
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High Current Buck Converter with wide input voltage [closed]
I'm currently building a powerbank with PD outputs that are capable of outputting 5 amps at 20 volts, but my battery pack is 33.6V (8S Li-ion). I've managed to find a possible buck converter IC (...
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Robotics Dual Battery System
Background:
I'm designing a general purpose robotics controller. The controller is split into two boards, a power board, and a computation / data handling board. The controller is intended to be ...
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Is it possible to chain BMS modules?
Let's say i have two 6S Lithium BMS modules (basically protection and balancing) and i want to create a 12S battery pack. Is it possible to chain the power lines of said modules?
Just curious
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Estimating SOC using coulomb counting with DSP
I am trying to estimate the SOC of a battery using the Coulomb Counting technique. I am implementing the following equation on a DSP inside PSIM:
$$
SOC[K] = SOC[K-1] - \frac{I_{Bat}}{Q_{Bat}}\cdot{Ts}...
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Establishing Safe Operation Range for Lipo Battery with Buck Boost Converter
I have a circuitry that I need to power up with lipo battery. I need to regulate battery to 3.3V with buck-boost converter, since LDO can not be able to provide required current output and causes ...
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What is the maximum voltage of a coin cell battery? [closed]
The nominal voltage seems to be 3V for a coin cell battery (e.g. motherboard battery), but what the maximum of a fully charged battery fresh out of a package from the factory? What is the theoretical ...
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Are my charging equations being used correctly in my lithium ion battery Python simulation?
This is a continuation of a previous question I asked (Are my equations correct for a simple lithium ion battery model in Python?). My issue now is I do not believe I am using the charge equations ...
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In a circuit schema, why the voltage at the battery anode is conventionally 0V while the voltage at cathode is usually the voltage of the battery?
I will try to explain where my question is coming from.
Knowing that voltage is the electric potential energy per unit of charge at a given point.
And knowing that electrons are pushed from - to go to ...
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Charging lead acid batteries in parallel? [closed]
I recently got my hands on eight 12V 9AH lead acid batteries. Could I simply place them in parallel and charge them with a battery tender without any special measures? Are there any risks involved? ...
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Using a 9V battery instead of a DC power supply
I have a DC power adapter that has the following specs:
Input Voltage: 100-240V AC, 50-60Hz, 0.5A
Output Voltage: 9V DC, 1.5A
I am interested in taking a 9V ...
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Switching battery and main power supply
I have Li-ion Battery (12.6V) and 15V power supply, also DC-DC buck converter set to 12.6V as charger for Li-ion Battery. My load can take both 12.6V and 15V. I want to use Li-ion battery as power ...