Battery Definition and 1000 Threads

hello everyone, I'm a battery pack designer, I'm very happy to join PF.

How do I calculate Watt Hours from the info on a battery: CyberPower Model No: CST150UC Input 120V, 12A, 60 HZ 1500VA/900W, 60 Hz USB-C Output 5Vdc, 2.5A Max 9Vdc, 2A Max USB-A Output 5Vdc, 2.4A Max Total Output; 30 W Max To carry it onto a plane in Canada it...

Hey everyone, I had an idea for making an aluminum air battery that mitigates some of the problems. The draft is quite rough but I just made it now and I can improve it as I go along. So basically the idea is the aluminum will cut up into large grains/pellets in a fuel tank. The pellets will...

Another thread (now closed) raised the question of whether it is a good idea or not to "whack" a Li-Ion battery that is no longer working. It is not. But the reasons for it being a bad idea are kind of interesting. (1) A modern Li-Ion battery is not a lantern battery of decades past. It has a...

I have a 6yrs old HP 17.3" laptop. I set it to never shutdown, but lately, it shutdown by itself when not using, I want to try to troubleshoot it before I go out and buy another one. 1) The battery seems to be dead, it has 0 charge. I pulled the battery out, put it back in a few time to clean...

I'm doing a 3S3P pack. My box can hold 9 18650s. It can also hold 3 18650s and 6 21700s. Is it ok to mix 18650s and 21700s in the same p pack? I would use the same 21700s and the same 18650s in each p pack. I would arrange them to maximize capacity. So say 18650 cells are Model A cells (making...

Milwaukee makes a cordless right angle impact wrench, 2565-20. As part of their M12 line of power tools. A YouTube channel tested the performance of the tool, with their different batteries. I'm having difficulty in understanding the observations. It seems that higher output current batteries do...

Hi all I have a ride on toy car for my 2 year old daughter and the battery died after not using the car for a few months. The battery was a 12v 7ah rechargable lead acid battery. I decided to upgrade the battery to a 12v 12ah one and having charged it up and fitted it in the car, I have lost...

First let us talk about a case where the battery gets discharged, I have a circuit with a battery and a load. The emf of the battery is 6V and the potential difference is a little less because the battery has internal resistance. When a charge moves from the anode and reaches the load it loses...

I am going to reason this out for a simple circuit with a battery (with no internal resistance) and connecting wires which can be considered perfect conductors. Please let me know if I am thinking correctly, I am quite confused by the overall working. An isolated battery has two electrodes...

Hypothetically speaking, if you wanted to prevent rust on your car frame, how would you wire your battery to your frame?

Hi everyone. So I am making a Ni-Mh battery , and for space constraints, I need to put 2 batteries in paralell + 1 battery in series with them. So if I get two batteries of 2100 mah in paralell I get 4200 mah, but if I put them in series with one 2100 mah battery , what would be the...

I am uncertain if this represents situation (a) or situation (b). i.e. is 2 = E-iR or is 2 = E? Or is the question ambiguous? Thanks!

Let's say I have an LR circuit. I understand the mathematical derivation of this but would like to understand it conceptually. Okay, so a battery is introduced (let's say 12 V). The inductor hates the change, so it induces 12 V in the opposite direction, opposing the battery. So what happens...

If a battery is in a closed circuit, we have an electrostatic field ##\vec{E}## from the positive terminal to the negative terminal of the battery through the circuit outside the battery. This field generates current. Inside the battery, the electrostatic field lines go from positive to...

Image from Wiley Intro Physics Textbook sample problem This was the given problem. In the diagram, one can see that the current flowing into each battery equals the current flowing out of each battery. Is this always the case, and why? If there was only one battery, I guess it could be...

Accepted thinking is that time slows as speed increases, relative to a non-moving reference frame. But supposing that the object approaching C is a ship in rotation around the earth, and on that ship is a laser mounted on a gimbal such that the laser is always pivoting and trained on exactly...

Using KVL we have ##\epsilon_1-\epsilon_2+iR=0##. It seems that ##\epsilon_1,\epsilon_2##, and ##R## are given and the only variable is ##i##. Thus, ##i=\frac{\epsilon_2-\epsilon_1}{R}## for the KVL equation to be true. However, it seems like when we think about what happens to this circuit...

Suppose we have 12V battery. Though I can solve electric circuits, there are some very simple practical concepts that are gaping holes in my knowledge. What does it mean for a circuit device to "pull a lot of current"? What is a simple circuit element that when I connect it to the battery it...

I use a 12V battery to power a DC booster circuit. After just a moment, my battery's voltage decreased, causing the booster circuit to also decrease its voltage. Is there any way to make the battery last longer without losing voltage? Thanks

For those that have to vacuum large spaces often have to use many different outlets and worry about running over their own cord. Is there a battery pack one can strap to their back to power a vacuum cleaner? Or would that amount of power tide to a person be dangerous?

Hi, So, PC powered of all the sudden, wont power on. Battery had not been charging when PC was plugged in. So, can I conclude neither battery nor power cord are working well? I guess my options for doing something to have battery recharge are limited, given PC won't power on. Do I have any...

Hello All : i had few suggestions about battery enhancement using some ideas which i had just abstract understanding not enough even to suggest discussion but i have this question why we dont fold the anode and the cathode into geometrical shape , wouldnt that increase the number of...

The solution is thus 0.69 ampere-hours, or 690 mA-hours. Now, as far as I can tell, an ampere-hour is unit of charge. That is we can convert it to coulombs (C). For example, if we have a current of 1A for 1h, then we have 1 C/s x 3600 s = 3600 C = 1 ampere-hour. This is my guess since the book...

TL;DR Summary: We purchased a 9v battery box and planned to wire it—in parallel—to 10 mini bulbs, assuming 10 bulbs drawing from the 9v would be more than enough voltage drop to not go up in smoke. We purchased a 9v battery box and planned to wire it—in a parallel circuit—to 10 mini bulbs...

Does anyone know a cheap(available on Ebay/AliExpress ) battery protection circuit board that has undervoltage/overvoltage protection and charging capability? I have a 3.7v Li-po battery and I need to draw 5 Amps from it.

Sorry if this is a very simple question but i have been googling and looking around for a straight anwser but can seem to find a solid answere or draw a solid conclusion from information I've reached. So I have a rgb led light for a car, the box says input 12vDC. if I wanted to set these up...

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For this problem, The solution is, I have a few questions about parts of the solutions, - Part(b): (1) Why do they assume that the capacitors are initially uncharged? Do they even need to make that assumption because it seems clear to me that we are finding the charge stored by each...

How is the load (variable resistance) adjusted in an automobile battery? Mechanically (potentiometer, rheostat) or electronically (digital potentiometer) or are both configurations possible.Can the load in a automobile battery be a three terminal divider (potentiometer) or is it almost always...

I would like to know when a alternator is charging a battery is the current flow a series opposing circuit......?

A suggested fix for a Roomba 500 series with a battery that won't hold a charge is to hold down the "spot" and "dock" buttons to "reset" the battery. (e.g. ) What, physically, does this do? Does it completely discharge the battery? Does it change some setting in the computer that...

Could a normal rechargeable battery (meaning the kind you plug into a usb port or electrical outlet) be recharged with a hand crank generator (assuming it was generating a sufficient voltage)? Would there need to be some kind of converter to make it possible, or just connect some +/- leads? I'm...

I am trying to determine how the addition of a counterweight affects the ##C_m-\alpha## (in longitudinal direction) graph for a model plane project, where the counterweight can be considered as the battery. Suppose we try to place the battery at the back of the current CoM. The new CoM will...

I moved to Kansas from Arkansas when my father got a job at the Sunflower Army Ammunition Plant in Desoto Kansas. Now that plant will be making Batteries for electric autos. I wish my dad was still alive to see this.

I was searching for a way to measure the remaining charge of a battery using Arduino. Most (almost all) of the tutorials are simply measuring the battery voltage using the ADC on the Arduino. The calculations are pretty straightforward after that — ##5 V## is mapped to ##1023## and ##0## is...

Panasonic is going to build an electric car battery factory plant in DeSoto, KS. Will hire 4000 jobs at the plant and another 4000 jobs throughout the state. IIRC, the factory will cost 4 billion dollars to build. edit: corrected spelling of DeSoto

I have a C-Pap machine, and I'd like to put together something to power it for a few hours if we have a blackout. Wiring two of the above lantern batteries together should produce 24 volts. But I can't find any info on how much wattage you can draw from these before the voltage will sag. It...

Have been busy working with a student doing a Physics prac to determine the internal resistance of an AA 1.5 V (nominal) battery. The basic formula being investigated is: $$Vt=E_{cell}−Ir_i$$ where ##Vt## is the load (resistive only) voltage, ##E_{cell}## is the emf of the AA battery, ##I## is...

My new Lenovo tablet has a "battery protection mode". This is useful for example when you want to leave it on charge almost permanently, in which case the protection mode will charge and discharge between 40% and 60% in order to maximize battery life. Is there an API that can enable/disable...

Google top result says Toyota is researching Fluorine batteries that they claim will have 7x energy density of LiIon. However my textbook table of reduction potential gives lithium as higher than fluorine. Any idea what they base their claims on? Thanks Joe

This is a confusing question. I am not sure if electrons flow through the battery from positive terminal to negative terminal against the electric field within the battery; or the electrons deposit on positive plate resulting in a chemical reaction that releases electrons at the negative plate...

Just wondering what would happen if a muon entered the LiH dense environment of a lithium battery. Could it explain the instances of spontaneous combustion of the battery in electric vehicles? Li + H => He

With a capacitor with a dielectric with the battery on, ##E_{total} = E_0 + E_i## ##\frac{Q_t}{dC_t} = \frac{Q_0}{dC_0} + \frac{Q_i}{dC_i}## thus, ##\frac{Q_t}{C_t} = \frac{Q_0}{C_0} + \frac{Q_i}{C_i}## since in a battery ##V_t = V_0, V_i = 0##, so either ##Q_i = 0## or ##C_i = infinite## but...

When I was 18 years old, I worked at an automobile repair shop doing oil changes and other light mechanical work. The automobile repair shop hired me for this work to free up their real auto mechanics to do more advanced automobile repair work. One time I was assigned the task of replacing a...

Hi! I want to start with saying that I'm not an expert on these type of problems, but I will be gratefull for some calarifications. I've heard that there's nothing in psysics that says that time travel is impossible. I want to make a case with the time traveling battery. Could be any mass with...

I’m assuming 6V is a suitable battery for such process. The terminals on this type of battery are different from what I’ve seen on other types. The positive terminal is “capped” with black plastic. With this cap intact, would I be able to generate electrolysis?

I have a 6 years old MacBook air, still running the OS of a couple of years ago. Lately, battery life is going down (around 4.5 hours of light/medium use) so I mainly use it as a desktop computer, connected to an external monitor. However, when I leave it in sleep mode (still on, but shell...

I have held the assumption that batteries supply electrons at the negative terminal and absorb electrons at the positive end for many years. However, after watching this video at about 3:30, it is said that batteries do not actually supply charged particles but that the battery only creates an...

I have few questions on the battery voltages for electric vehicles. Some vehicles operate at 48V battery and when i read the standards regarding these they mention above >60 V is hazardous and may lead to electrical shock and shall be avoided under all conditions. But i also see batteries with...