Stack Exchange Network

Stack Exchange network consists of 174 Q&A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers.

Visit Stack Exchange

Questions tagged [batteries]

An electric battery is a device consisting of one or more electrochemical cells that convert stored chemical energy into electrical energy

0
votes
1answer
51 views

Summing up batteries

I am a little confused, shouldn't I take into account the maximum battery voltage when trying to add-up batteries in order to achieve certain voltage? For instance if I want to drive a 48V 1000W DC ...
0
votes
1answer
37 views

Two different power sources with same voltage and current producing different results

I'm working on a little 3D printed robot (Otto DIY) with an ESP8266 and four servos, and I need to feed it with batteries. As a first thought, I considered some 18650 cells I had lying around, with ...
24
votes
5answers
9k views

How could have Banksy kept an RF receiver running for 12 years? [closed]

I'm talking about Banksy's "Girl with balloon" painting that shredded itself at auction. I think the general consensus is that he didn't, and that it was set up before the auction (or a couple years ...
0
votes
2answers
67 views

Connect 3 Lithium Polymer battery with different capacity in parallel [closed]

I am working on an IoT product with has a total current requirement of 1.3 A at the peak. Due to space constraint, we decided to select Li-Po battery with capacities one with 600 mAh other two with ...
0
votes
1answer
22 views

Charging a battery

So we have a charger outputting V volts and I Amperes and two rechargable batteries of the same capacity Q coulombs but different emf's V1&V2. Which battery would charge faster? Approach: So ...
0
votes
2answers
52 views

In Impedance track algorithm, How is resistance is related to soc(state of charge)?

In impedance algorithm for battery capacity, why we are calculating impedance and why it important to know impedance for SOC(state of charge)? 2.I doing some research on algorithms which we have,so,...
1
vote
1answer
41 views

How to charge a battery when the charging socket is broken? [closed]

First of all I'll explain my situation: I own a Bluetooth speaker, more precisely this one: http://www.leicke.eu/en/products/EP18108 Due to my clumsy hands it fell while the USB cable was connected ...
0
votes
2answers
74 views

Can I test if a battery is connected to a circuit?

I have a 12 V rechargeable lead acid backup battery that is connected to a circuit. When the battery is not in use there is a constant 12 V applied for charging, and when the battery is in use there ...
0
votes
1answer
461 views

Calculate battery state of charge percentage

What is the correct formula to calculate battery state of charge percentage based on the battery type (12v, 24v, 48v and so on) and the current battery voltage. For example if I have a 12v battery ...
0
votes
1answer
65 views

Rebuilding Makita NiMH Battery with Cells of Bigger Capacity. Will it Charge Properly on the Old Charger?

This is for a Makita 6932FD impact driver. It runs off a 14.4V NiMH battery of 2.6Ah. I ordered sub-C cells (with solder tabs, don't worry :P) that are 4.2Ah. I was reading about DIY NiMH chargers ...
1
vote
1answer
38 views

Charging Multiple 3S Lithium Ion Packs Together

This is my current situation, just to provide background: I wanted to build these small battery pack modules that were 3S2P as a modular system, where a pack could be used with many different ...
-2
votes
1answer
424 views

Would you get electrocuted if you touched a car battery? [duplicate]

Lets say that you have a connected car battery. If you remove the negative lead first and then touched it would the current go through you to the earth (GND)? What is i then attached a wire which is ...
1
vote
0answers
44 views

Is current draw the same when powering a device directly from batteries or from a dc-buck converter?

I’m having a strange problem here: When I use two AAA batteries to supply a small slave flash, it charges in 10 seconds, with 1.4A instant draw for the first second and smoothly reducing current draw ...
0
votes
3answers
52 views

Convert Battery to AC @ same voltage

I have some LED fair lights that run on 30V @ 0.4A supplied from an AC mains supply. They have been wired to flash using some form of notification to the AC (I'm not interested in them flashing). I ...
0
votes
0answers
38 views

How effective is CID and PTC protection on batteries?

There is a source that states: 18650 batteries sold in the US are required to have CID and PTC protection. I've read that CID is just an insulation layer, and PTC is a resettable fuse which ...
0
votes
1answer
61 views

Any way to use external power for multi-meter instead of the 9V battery?

I have read discussions on NOT to use external power, say an ac adapter, instead of the 9V battery. But what if I mostly do is to test for continuity, would it be acceptable in such case? What other ...
1
vote
1answer
55 views

Charger, load sharing and Fuel gauge

I'm designing a battery powered circuit where I would like to charge the battery via USB, and monitor the remaining battery capacity during operation. I'm using the following IC's: MCP73831 (charger)...
0
votes
1answer
50 views

Remote control's battery bay issue, no voltage at the end of circuit [closed]

I have a remote which needs 6 AA batteries, I put fresh AA batteries in and I tested via volt meter and at the last battery's negative connection is showing zero reading. The same battery's positive ...
0
votes
1answer
57 views

Can I use a van battery with an invertor to power a food warmer?

I'm thinking of using an inverter for a food warmer (1700/2000W). I'll be warming it up through the mains at first and then using the inverter for 30 min to 2 hours max. Would be ok to run on a van ...
-5
votes
1answer
104 views

Battery capacity calculation/method [closed]

While calculating battery power capacity requirement for a circuit consisting of multiple loads having different power consumption, how should one proceed to avoid any error? How it is done in ...
0
votes
1answer
43 views

Relation between terminal voltage and charging speed in Lithium-Ion/Polymer batteries?

I tested charging a 5200 mAh (20 Wh) battery at 10W. Its charging level at the beginning was 20%. The terminal voltage was 3.68V. Now, I applied 10W of charging rate to the battery. The terminal ...
0
votes
1answer
73 views

12 volt 8000 watt battery discharge protection

We built a home in a country where electricity is a rare ressource. In order to have energy available all day we bought a bunch of solar panels and several 12 volt batteries. We then used a 8000 watt ...
-1
votes
1answer
59 views

Battery Run-time/capacity calculation

Problem is to find the difference in run-time between: a. Using 12V 10Ah battery vs 24V 5Ah battery. PS: Load is rated at 12VDC and 24V to 12V step-down conversion is available.
0
votes
1answer
86 views

Convert something that runs off two D cell batteries to instead run off a car battery

I do not know much, but I have a portable shower (http://help.venditiogroup.com/support/solutions/articles/6000178636-zenvida-portable-tankless-water-heater-outdoor-shower-260-pcwh01) that I would ...
2
votes
1answer
177 views

Why Peukert's law is always ignored in battery(lead Acid) guides available on Internet?

I am doing battery calculations for off-grid solar panel. I don't get that why battery guides on Internet always ignore Peukert's Law for batteries of solar panel. I want to have good approximations ...
1
vote
1answer
27 views

Tapping power from series of solar panels

I'm developing a device that runs off 24V DC. I'll be installing it at a client's site who has arrays of solar panel, with 24 panels in series, making it a 1000V system. Can I tap one panel from the ...
0
votes
1answer
53 views

How to tell a battery's ideal charging voltage with a circuit?

simulate this circuit – Schematic created using CircuitLab I've been looking to build a universal charger for my laptop and phone, and I'm wondering; is there a viable way to adjust the input ...
0
votes
2answers
84 views

Getting trouble powering a LED strip with battery

I'm trying to build a portable LED light and things are happening not the way I wish to. I have a Sumbulbs 12036 LED COB Strip. This LED works with DC 12-14V voltage, it has 10W power and recommended ...
-1
votes
1answer
92 views

How to implement coulomb counter method for battery capacity using any micro-controller? [closed]

I trying to implement coulomb counter method in any micro-controller. suggest me, any circuit ? Or Any give idea how to implement?
-1
votes
1answer
122 views

How to design embedded battery charger circuit

The system is battery powered. When the battery is low, the user can connect the AC/DC adaptor to the board, then the DC input can charge the battery through the charger circuit. I don't have the ...
0
votes
2answers
83 views

Battery power for project [closed]

Please could someone suggest a suitable battery for a specific project. I need to power a 40 W 12 V car headlight bulb for 10 sessions of 3 or 4 h each time, recharging after each use. I have ...
0
votes
1answer
180 views

Battery Charge and Discharge Time

I am doing a case study on battery back up of a wind system with the following specification: System size: 10 kW which runs continuously for 5 hours per day. Battery Calculations: Battery type: ...
-1
votes
2answers
85 views

Do electronic devices require more current when alkaline batteries goes low?

I know that alkaline batteries' voltages go down when they're at low charge (from 1.5V~1.7V to 1.0V). For typical electronic devices like remote controls or bluetooth mouses/keyboards (that uses two ...
0
votes
1answer
109 views

Why doesn't this battery explode?

So I know that it sounds very stupid, but I'm trying to test the limits of a 12 dollar bluetooth speaker. I disassembled the whole speaker and replaced the original 3 watt speaker with a 70 watt one😂...
1
vote
3answers
113 views

How to connect LED strip to be powered by charger and batteries

I plan on using it mostly plugged in, batteries are there just for extra mobility and won't be used most of the time. Don't know lot about batteries so in first scheme I added a switch (pos. 1 ...
0
votes
2answers
116 views

How to measure output voltage of this Li-Ion battery circuit?

I've designed an AtTiny85 based Lithium-Ion battery protection/boost circuit that monitors the battery voltage and cuts the battery power to the external powered circuit when the battery dips below a ...
0
votes
2answers
60 views

What should be the V specs of a step down transformer for a 10amp car battery charger

I was looking to create a 10amp manual charger with variable voltage and current option for flooded lead acid battery (normally used in cars). I only know some basic electronics and usually make ...
1
vote
1answer
70 views

How to calculate capacity of a battery from the readings of current and time?

The requirement is to compute the capacity of the battery in order to calculate the capacity degradation. The input which can be acquired are current, voltage, relative time, battery level (in terms ...
0
votes
1answer
86 views

Discharging 18650 battery at constant rate

Hello I am planning to do some tests with a 18650. In these tests my goal is to measure required time to discharge them with different discharge current rates (1A, 2A, 5A and so on...) The op amp ...
0
votes
1answer
66 views

Difference between more batteries and boosting voltage

For example if i need 18V for a project, what is the difference if i use 2 9V batteries and 1 9V battery boosting it to 18V? Thanks in advance.
2
votes
0answers
194 views

DIY 4S Li-Ion battery pack

I am in need of some help designing my battery pack. I have a few concerns, mostly around charging. My plans consist of using a microUSB boost converter to bring the voltage to 16.8V for charging. ...
0
votes
1answer
35 views

Battery sizing for motor?

I have a question regarding battery sizing and solar panel sizing ,I am not from an engineering background that's why i might need some help with this. I want to run a 24vdc gear motor 180W 11.5 amps ...
2
votes
3answers
449 views

Car battery (lead acid) discharges much, much faster than it charges?

Let's assume a lead acid car battery (12V, 50Ah, 250A output). According to BatteryUniversity article BU-403: The charge time is 12–16 hours and up to 36–48 hours for large stationary batteries. ...
1
vote
1answer
124 views

How were Power Bank limits decided by airlines?

Why is a 160Wh power bank considered safe to carry on board, but not 170Wh, for example? What defines this maximum safety limit, how was it determined? Obviously airlines across the globe have agreed ...
0
votes
1answer
107 views

Use 36v battery with step up converter for 48v kit

I have an e-bike motor ( bbs02 48v 750watts ) which requires 48v battery. I also have a 36v 13ah ebike battery. Opening the battery and changing cells connection to make it 48 would take lots of ...
1
vote
1answer
145 views

How to charge 4 NiMh AA batteries with solar cell

I have a nice 6V solar panel and I was thinking to use it to recharge a 4xAA NiMh battery pack (nominal voltage 4.8). Is it enough to put a series diode (0.7v) to drop the voltage, or do I have to ...
1
vote
0answers
34 views

battery life of rechargeable lithium battery

I am trying to determine the life of a lithium rechargeable battery (approximation) before a complete replacement is required. From Panasonic's datasheet, I see that at avg. 10% discharge, it is rated ...
0
votes
1answer
89 views

5V Step Up Converter Drops Voltage to 2.3 Volts when Connected to Device

Recently I combined two 18650 batteries in Parallel, and attached the output of the Paralleled 18650 batteries to a 5V Step UP Converter. Device draws 5V 4a. Here is a picture to the step up: ...
0
votes
1answer
132 views

touch negative and positive side of battery briefly

I on accident made a brief connection between the positive and negative size of a 3.7v battery. Connection was for less than half a second but I saw small amount of smoke come out from the wire. Can ...
1
vote
3answers
76 views

Powering a PC monitor with batteries

So, this is where I am at currently( no pun intended). I am assuming that with an inverter for both components and 3 - 4-18650 cells in series - in parallel rated at 4800mAh would be good enough? Ill ...