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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123 views

Is this circuit damaging my microcontroller?

I have a circuit which is designed to set off one of two e-matches at a given time as controlled by a microcontroller. The circuit itself functions as intended. The potential problem is that after ...
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0answers
38 views

How can a DC-DC converter kill SLA battery voltage on light load?

I'm running a small 12V-500V DC-DC converter (shown) on a purely resistive 50mA load. I was getting weird behavior off my bench 12V DC supply so I plugged in the SLA battery shown. I connected a ...
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1answer
46 views

Should I connect solar panels in series or parallel for my charger?

I am making a solar charger for 3 AA batteries. I have two 6 volt 100mah solar panels. Will it be more beneficial to connect them in parallel to have more current or in series to increase the voltage? ...
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3answers
124 views

What is the purpose of MOSFETs in this schematic?

On the main power line there are two MOSFETs but for what reason? The MOSFETs in question are Q1 and Q2.
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0answers
30 views

need help designing a battery charging circuit for aio tablet pc [on hold]

Hi so im in the process of designing/building an all in one tablet pc with a wacom digitizer however i have a problem, i need it to be able to run off a battery as what is the point of a tablet if ...
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1answer
40 views

NiMi battery quickly looses charge [on hold]

My 5 cell NiMh rechargeable battery is fully charged at 7.2 volts when a load of <0.75 amp is applied the battery quickly looses its charge, the motors do not run at all when fully charged. The ...
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3answers
55 views

Sizing battery cables

I'm confused about the sizing of the battery cables for a UPS system, When the battery is discharging the voltage decrease and current increase to a maximum value (which depend on the end of discharge ...
0
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1answer
55 views

Life of a heated coil using a 9V battery [duplicate]

I've been looking into heating a nickel chromium wire with a 9V battery for one of my projects. Can anyone feed me an equation for calculating the life of the battery? I'm sure it will include gage of ...
1
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2answers
69 views

Best way to deal with surge in current from DC motors

I have a Li-po battery 12V 9800mAh (typical current 2.4A) which powers a 4WD drone using 4 DC motors (which I have not yet characterized). Driving the motors from still to max speed without ...
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0answers
62 views

Many questions about charging a lead acid battery

Well, I have a 12V 9AH SLA Battery, and I use a 7815 + a diode in series to charge it, (I really wanted to build a charger using the L200 or the LM317 but I couldn't find any of those in my city). So, ...
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0answers
20 views

Rest time for testing lipo cells

My university's student electric racing team has to test a large number (250) of lipo cells before using them in our electric car. Our testing methodology will be approximately like this: ...
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2answers
46 views

Battery Life calculation

I am doing some calculations to determine battery life under certain load conditions. As such I have turned to the internet and found this online calculator by DigiKey. The calculator used the ...
0
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2answers
31 views

Trickle charging a Li battery from motorcycle battery?

Sorry if this doesn't belong in the forum, however I'm unsure of where to start and am rather clueless with electronics, but keen to learn more. Essentially I would like to charge this GPS device ...
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0answers
4 views

Create Car Battery Load from Smaller Batteries [migrated]

I want to determine if it is possible to chain together smaller household batteries to produce the equivalent output of a 12V car battery (temporarily). There is a practical reason for this bizarre ...
0
votes
1answer
106 views

How do I measure current with a microcontroller

OK, having given myself a crash course in op amps, I think I've got it figured out. I am looking to build an in circuit battery monitor, and I wish to measure the current being drawn from each ...
0
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1answer
41 views

Resources for batteries? [closed]

I was wondering if someone could recommend a textbook or some online resource on batteries- working with lifepo4 for the first time and I was wondering what all I should be worried about and what all ...
0
votes
1answer
77 views

Best way to deal with voltage loss in batteries

I'm doing a project with Arduino. I have a small Arduino board that every so often takes measurements from a sensor, but it's idle most of the time -- consuming 6mA. I want to use a small battery to ...
3
votes
1answer
62 views

How does a battery balance and protection circuit work?

I am building a 4S LiPo battery pack that I would like to incorporate in a portable speaker project and I need to make sure the batteries will never require maintenance beside replacing them ...
1
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1answer
74 views

How do you choose between 450 V vs. 750 V as a power source for your EV? [closed]

I am wondering what the decision factors are to help choose between 450 V DC and 750 V DC power source for an EV (electric vehicle). The propulsion system is available in voltages between 350v and ...
2
votes
2answers
85 views

Charging time of lithium ion batteries

I am charging a 430mAh lithium polymer battery at 1C using BQ24232 charger IC (from Texas instruments). The charge terminates within 1 hour 20 min with battery voltage showing 4.17V. On research I ...
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0answers
53 views

Why doesn't battery packaging and advertising allow “unit pricing” comparison? [closed]

Why do battery manufacturers (mainly of "flashlight" type batteries, AAA, AA, C, D, 9V, etc.) not (and apparently are not required to) specify the objective ENERGY content/density of their products, ...
0
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1answer
124 views

Arduino and GSM Module running on Li-primary batteries for years

For one of our projects we need to run an Arduino board + GSM module (SIM800C for example) for many years on batteries without recharging. The Arduino should be in power down mode for 99,99% of the ...
1
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1answer
29 views

Solar cell charging and battery chemistry for low power 2.4-3V supply?

I've recently been looking into the possibility of using an amorphous silicon solar cell (like they have in calculators) to supplement my very low power BLE system's current consumption to extend the ...
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2answers
41 views

Large Battery Cell mounting in Enclosure

I am trying to figure out the best way to mount a battery like this (http://www.batteryspace.com/polymerli-ionmodule37v10000mah37wh85arate-prewiredwithpcbpl9059156.aspx) onto a 8" x 6" PCB. There do ...
0
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1answer
47 views

Battery charger disconnection

In modern devices (mobile phones, tablets, laptops) the battery charging current is automatically switched off when the battery reaches 100 %. After being disconnected, the power supply cools down. It ...
0
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1answer
28 views

DS2438 battery monitor: how to connect load

I am looking at the datasheet for the Maxim DS2438 battery monitor and am confused by this circuit diagram: How would the load be connected? If connected between battery + and circuit ground this ...
0
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0answers
23 views

AGM Battery won't hold charge while powering - voltage drains

I have a 6V 2.9Ah AGM Sealded Non-Spillable Battery. When it's charged, it will hold and maintain almost 6V. When I connect the battery to the light that it's supposed to turn on, it still holds it's ...
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0answers
17 views

Arduino with wifi shield and 5AA batteries current draw [migrated]

Arduino uno with official Wifi Shield take 5 Volts. Arduino lights up as it should when powered but the WiFi shield is dead the l9 doesn't light up but works fine when arduino is connected to usb ...
0
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1answer
35 views

Combining single cell LIPO chargers into a multi-cell charger

I have a 2S lipo battery that I want to charge. Normally, I'd charge it with a balanced 2S lipo charger like this, but for my application, I want to embed the charger in the device, and consumer ...
0
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3answers
78 views

(Capacity 20hr: 65AH) Does this mean 65amps per hour for up to 20 hours?

Cranking Amps: 675 Im trying to find a good battery for a project. That part where it says "20hr" keeps making me rethink what i sorta hope it means.
1
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1answer
42 views

Battery charger with load sharing for portable Raspberry Pi 3

i'm doing portable Rasberry Pi 3 and i need help choosing the right battery power system requiered for the project. The project has: Raspberry Pi 3. Normal power consumtion around 700 mA with peaks ...
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2answers
48 views

Power for portable project

I decided to rip apart a cheap super Nintendo and wire it to a small screen. I am using it to learn more about electronics, practice soldering, using an oscilloscope etc. One of the challenges I ...
0
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1answer
44 views

DIY 18650 charge pack questions

I've tried searching through existing topics but haven't found an answer. I'm a beginner enthusiast. I have a couple of questions that I would appreciate input for. My plan is to make a battery ...
5
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2answers
191 views

Lithium coin cell battery showing randomness in voltage

I have a CR2032 coin cell battery and using that I am operating a BLE 4.1 module. When I connect a fresh battery in to the module the voltage shows 3.3 V, and after continuous communication with ...
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0answers
23 views

Premature battery discharge

I bought a brand-new 7.4V 3000mAh 20C Turnigy lipo battery, and I'm using it to power a Raspberry Pi through a 90% efficient 5V UBEC. The Pi consumes on average 600mA, so I was expecting the battery ...
0
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0answers
61 views

DIY Powerpack 18650 4s3p 14.8V charging

I plan to make a portable audio system with 4 speakers and a subwoofer which are driven by a 12v TDA2030A 2.1 Amplifier. Everything is already packed in a small enclosure (approx. 30x15x30cm) and ...
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3answers
117 views

Create a circuit with 3 identical light bulbs that all have different brightnesses

I'm learning about circuits in my physics class, and we've been given an assignment to create a circuit that can only use 3 identical light bulbs that should all have a different brightness. I've ...
0
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1answer
107 views

What is the fastest way to drain all the charges of battery?

I need to build battery draining circuit which must finish off battery's charges as fast as possible. I've designed one, but not sure is it optimal one or not? I decided to connect single R to battery ...
0
votes
1answer
79 views

Is it wrong to charge a laptop/cellphone battery when the device is on? [closed]

I always try to charge my laptop or my smartphone after turning them off. I feel that leaving these devices charging when they are on could be detrimental to them. But... is it? And whether the ...
0
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2answers
60 views

Simple stand-alone power supply for an arduino device?

The world of diy electronics is pretty new to me, but I have a sparkfun kit, a temperature sensor, and a new greenhouse that I want to learn the behavior of. Basically, I want to record the ...
1
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1answer
316 views

What protection circuits do laptop batteries come with?

I am currently using an old lithium-ion laptop battery pack for my portable sound system. The battery seems to work pretty well for its age. I simply hooked up a cable to the positive and negative ...
0
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0answers
5 views

How much energy does RSA consume if implemented on Arduino or Raspberry Pi? [migrated]

is there any way to know how much energy does RSA consume if implemented on Arduino or Raspberry Pi ?. Thank you.
0
votes
1answer
39 views

Does the voltage of a solar panel have to be greater than that of a battery pack to charge it?

I have a 6 volt solar panel and a 4.8 v battery pack(4 AA nimh). Will I be able to charge the pack? The solar panel is 100 milliamps and batteries 2300 mah.The solar panel is like the one here: ...
0
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2answers
54 views

What is the difference between charging batteries in series and parallel?

For example, if I have a charger that supplies 300 milliamps: Will it take a bit more than 3 hours to charge a 900 mAh AA battery? What if I have 4 AA batteries in series? Will it still take 3 ...
0
votes
1answer
35 views

Does it matter what the input voltage is to a DC/DC step-up converter?

I have a converter that outputs 5v and 1 amp. The input voltage can be 2.5-6 volts. Does it matter as long as it is in the range? Also, will the current draw from the batteries differ if I change the ...
0
votes
1answer
38 views

Do you need to use different materials for a battery busbar?

I'm interested in building custom Lithium Ion battery packs out of reclaimed 18650 cells. I've seen several videos of people doing this and some of them use copper for the positive busbar and brass ...
0
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1answer
50 views

DIY battery Pack Cell amperage difference

I have individually tested the capacity of ten 18650 batteries with my iCharger 4010. My question is, how much ampacity difference is ok when packing them in parallel ? The following are the readings ...
3
votes
1answer
86 views

How long should 8, 1.5V batteries last for?

I purchased a GPS tracker from Amazon and instead of wiring it to the car battery I would like to simply attach my own power battery pack. I am a complete noob when it comes to electronics and I ...
1
vote
1answer
69 views

Many-year-old laptop batteries: safe in my closet? For how long? [duplicate]

I have laptop batteries that are a few years old and lost their charges, but which I've still kept "just in case"*. However, I've heard that letting them lose all of their charges can be dangerous. ...
3
votes
1answer
86 views

How much nickel is in a NiMh battery?

How much nickel is in a NiMh battery? For example, how much nickel is needed for a 100Wh NiMh battery? How much nickel is in a common AAA NiMh battery? This question is equivalent to: How much ...