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Power bank

Hello everyone I recently found a 12v 9a.h battery in my stuff and now i decided to make a portable power bank with it.this is what i am thinking about:i want to make a portable power bank with several voltage outputs for using in car and etc. 1- I want to get a 5v output and use it to charge my devices when I am in a car.2- i want to connect some power led lights so that i have a light bar.3-maybe I also connect an amplifier to it to play music when walking or etc.now that you understood what i want to make these are my problems:1-when the battery slowly drains and the input voltage decreases will the output of the charger module also decrease?2-different devices need different currents for charging for example my tablet needs 2amps while my phone needs 1 amp. do i need to set the output current to any special value?3-what kind of solar panel will be suitable to charge the battery?

Question by Electronic guy    |  last reply


Circuit for power bank? Answered

Hello, Need a circuit design for the following requirement. Checked online available circuit designs but not sure if they meet all needs.  Looking for circuit design as per following details. 1. It will have one or two, 3.7 volts 2600 mah 18650 lithium batteries 2. Batteries will be charged using smart phone mobile charger or solar panel 10 to 20 volts and around 500 mah to 1 ah input 3. Will have mini usb connection for the same on pcb 4. Circuit should have battery level indication. While being charged, when they are fully charged LED should turn on indicating battery full. Also there should be one LED to show that the charging is in progress. When the battery charge drops below specific level another LED should turn on. 5. If we use 2 batteries then they will be connected parallel 6. Output voltage of the batteries should be 5 volts (so step up is required) and current should be appropriate for mobile charging 7. There should be provision for 2 USB connections. Load can be mobile charging / USB mini fan / USB mini keyboard LED (could be 2 at a time) 8. Circuit should be safe enough so no damage is caused to batteries / load etc.

Question by rahuldj    |  last reply


HOW TO MAKE SMARTPHONE POWER BANK AT HOME ?

I have samsung s duos gt s7562 and the big problem is its battery. whenever i have to go out for a day long, i have to suffer for its poor battery back up. in market several power bank is available, but its costly. i want to make myself. i need atleast 3000 mah capacity power bank. So what should i do ? please tell me.

Question by pprasara    |  last reply


NiChrome Power Source? Answered

So, I'm doing a project that needs to boil maybe 8-10 drops of water very quickly. I was thinking of using NiChrome wire to do this as in the included diagram (sorry low quality, MS Paint). However, I can't seem to find an appropriate power source. So, I need some easy to obtain powersource that is also relatively small. Something like batteries, a capacitor bank, or anything similar. Remember, it has to be able to boil of those 8 drops pretty fast, lest they condense in another part of the pipe before the desired pressure is reached. 

Question by LiquidLightning    |  last reply


Recharging a `battery bank

Im looking for a dc motor that will carry a load of three 24v 100a alternators and a suggestion of what size and type of batteries will carry the dc motor. NOTE one of the three alternators purposes is to recharge the batteries powering the motor. Please help with a suggestion of what type of motor to get, the voltage or hp of the motor and what size battiers will be suitable to carry that motor.Thank you

Question by promisedominicakpan    |  last reply


Coilgun Capacitor Bank? Answered

I am building a coilgun for a high school project. The capacitors for the original design call for 2200uf 400v capacitors, but these are too expensive. I found some 1000uf 200v capacitors, would these still be powerful enough if I run 5 of them in parallel. Does the voltage make the coil stronger or is it the capacitance. My coil specifications are; 16 AWG 4 layers and 25 turns on each layer

Question by joselalala    |  last reply


My Capacitor Bank

This is a little project I've been working on for some time now, playing with capacitors to see what kind of sparks I can get. I finally decided to build a mounting board for them and glue them all together. You'll see before I glued them in, as I was counter-sinking holes for them to sit in. So far I have MOST of them wired together, in parallel, but I only hooked up the larger ones until I get all the "bugs" wrinkled out. I'm also using a relay circuit to switch the output from the capacitors (so I don't fry myself while they're charging). I have it set up with a 2-way toggle switch, so when I hold the switch to the right, it charges my capacitors, and when I flip it to the left, it triggers the solenoid, and I can then discharge the capacitors however I want. Right now I'm in the process of finding the right power supply, as I have both the relay, and the capacitors charging off the same 12V (1A) wallwart, but it's not enough juice for what I want. Enough to burn little holes in tin foil with the sparks, but It's just simply not dangerous enough for me! Me and nachomahma are working out something so an update will ensue! 

Topic by Punkguyta    |  last reply


Charging a 8kj capacitor bank

Hello I have a 8 kj capacitor bank and am looking to charge it with dc power I was wondering if I could use a power supply such as this: http://my.rs-online.com/web/p/embedded-switch-mode-power-supplies-smps/8399698/ Any feedback will be helpful Thank You-TDC

Topic by ThinkDesignConstruct    |  last reply


Power source for coilgun? Answered

I have built 2 coilguns already using a camera circuit for charging the capacitor bank, but because it is a disposable camera, the quality of the circuit wasnt very good so it stopped working like in a week or so,, so i was wondering if i could build a circuit for charging a capacitor bank (so i wont need to buy any more cameras), but i've already looked in a lot of pages for a schematic but i've got no luck anyone knows how to build a circuit for this purpose? i do not have a lot of experience in building circuits, thats why i dont figure it out myself thnks

Question by tato312    |  last reply


How to make a 230v AC power bank?

I would like to make an AC power bank but don't know exactly all the parts to get any help.

Question by OTKZuki    |  last reply


Please help Electronic (problem in power bank)

One of a resistance it's blow up in the power bank and i don't have the number of it !! and I could not find any scheme for this Motherboard of power bank and chip that use in this power bank is mt4606 and name of this Motherboard is yd178_b

Topic by maatoubi    |  last reply


Power Banks vs. ac wall outlets

I've observed in many power banks, that they charge up my phone a LOT quicker than a conventional ac adapter plugged into a wall socket. Why is this so? Many of my friends share the same observation. I'm building a simple power bank myself, and I want to make sure I can enjoy this feature when I use it too. I plan to use this instructable as a guideline with some modifications: https://www.instructables.com/id/Rechargeable-homemade-Power-Bank-super-Easy/ I'll be using four 3.7V batteries in parallel and stepping it up with a step up converter, so that the mAh value gets added up (forgive me if I'm wrong, but I believe mAh adds up when batteries are in parallel). Will this arrangement give me faster charging times like the power banks available in the market? Is it a safe circuit? Please suggest as I am eager to build this :) Thanks in advance :)

Topic by AshwinN3    |  last reply


Could a 12v LED light strip be powered by a portable power bank

I don't know the exact specifications for my LED light strip but i know a 12v 2500mah lithium battery powered it for at least 2 or 3 hours, unfortunately it was a crappy Chinese knock off battery that damn near blew itself up after repeated use and i can't find a replacement that doesn't look like exactly the same battery. with that in mind are there any small power banks with a 12v output that i could use? or is there some means of boosting a 5v output power bank which seems to be the most widely available type?

Topic by ambientvoid    |  last reply


Capacitor Power

I want these so badly, and I live relatively close (about 300 miles away).http://cgi.ebay.com/Qty-46-Pulse-Capacitors-7000v-230uF_W0QQitemZ200268515465QQcmdZViewItem?hash=item200268515465&_trkparms=39%3A1|66%3A2|65%3A15|240%3A1318&_trksid=p3286.c0.m14You can make one heck of a capacitor bank, releasing almost half a megawatt in a split second.My only problems:I don't have 1600 dollars, crycry.These things are so large that if I were to line them up side by side (so that the thinnest parts create the overall thickness) it would be 25 feet long, 14 inches wide, and almost a yard tall. THE POWER BOGGLES THE MINDI'm so mad, if I was an adult I'd buy these in a heart beat... sigh... deal of a life time... I hope not...and best of all, they are PULSE CAPACITORSthoughts? comments?

Topic by guyfrom7up    |  last reply


LED Power supply question

I've got an idea to build a LED light strip for some decorative lighting under a couple of shelves, but it's been more than a few years since I've used my GCSE-level electronics knowledge and I could do with a bit of advice regarding PSUs and parallel connections. I'm thinking of using  two banks of 10 of these LED packages powered by a wall-wart type 12v PSU.  If I wired the individual banks in parallel would I be right in thinking that that would be a current draw of 200mA per bank since each LED has a 20mA requirement, and if both banks were connected to the PSU in parallel I'd need a PSU capable of supplying at least 400ma?

Topic by megahurts    |  last reply


How to make power bank with 8 rechargable AA batteries?

I'm a nobody at electronics, electricals and stufs. well i have some rechargeable batteries for some reasons,. 2 of my friend has a portable power bank for their phone. then curiously thinking if i can make that kind of stuf.. (DIY),.. if it possible please help me make this... my AA batteries is 1.5V with 500mah of power if i'm right. , then multiply by 8 so that will be 12V with 4000mah of power? right?. then i want this to charge my phone... recently searching i need to drop the voltage to 5, because if not, my phone battery will or might explode., then my phone will be damaged?.. so i need to make a circuit,, then that my problem, i dont know any thing about resistors and things like LM317, just i don't know anything about that.. i need it be able to be recharge and charge my phone, so here's another question, expect the wee did make something like that, then how will i be able to charge it?, it's 12v right from the inside? right?.. that all, hope we can make something like this,, if there's a related post, which has been already answered, if this is not possible.. That all.. Advance Thanks for helps... 

Question by ZoneOne26    |  last reply


Capacitor bank for Coilgun help please!

I havetwo 680 uF capacitors, rated for 200 volts.. And I want to use a disposable camera charger to charge them both. The camera charger stops at 300 something volts, and when I wire them up in series, I get 400 volts, right?.. I want to charge them and discharge them into a coil of wire to launch a projectile at a fair velocity. , I can work with up to 10k wraps of wire, and i have only two capacitors and a major one.. First 2: 680 uF 200v 680 uF 200v Major one: 180 uF 400v Now I imagine I'd get more joules with the two smaller ones than the big one because of the microfarads, right? These specific type of capacitors are made from Elite, and are electrolytic I think, and I got the major one from a computer CRT monitor, and the two smaller ones from a computer power supply.... I also have a 3.3uF 50v capacitor. Now the question is: Can someone help me add these together to increase maximum joule output? I want to hook up the two 680 uF 200v capacitors in series to get a maximum voltage of 400. Then I want to add the major capacitor, which is 180 uF in parallel with the two other capacitors to increase microfarads, in this case, it'd be: 680 680   + ------- = 680 (because they are in series) ------- + 180  = 860 I want two capacitors in series, and the major in parallel, increasing voltage to 400 volts, and the major capacitor doing nothing but adding capacitance (IF possible) Sorry, this is alot to ask for you guys to answer, If none of the above can work, What would work better, the two 680 uF's in series, or one big 180 uF 400 volt capacitor? I apologize if I cannnot explain my question properly.... it's very hard to understand capitance and series/parallel blah blah mumbo jumbo. Thank you.

Topic by Justdoofus    |  last reply


Charging HV capacitor banks

I noticed that recently a lot of users are looking on information on how to charge capacitor banks. Not going into the legal aspects here when it comes to coil guns, EMP's and similar applications... I do have a few options at my disposal depending on how fast the charging needs to be but for serious applications with high power levels, fast charge rates and so on it soon becomes very technical. The differences between the US mains power and the rest of the modern world only complicates things here. So I was wondering who already build some decent cap charger based on inverter technology and if these people are willing to share their info and schematics for reference - if you already have an instructable explaining it a link to it would help heaps. Considering the costs of high performance caps circuits with proper protection against overvoltage and with good current limiting properties would be prefered over simple circuits that could damage the caps. Thanks for your help!

Topic by Downunder35m  


help me to made my own power bank

Can i make power bank with button cells battries ?

Topic by alireza8858s    |  last reply


how to make a power bank to charge your laptop?

I have an idea to make a power bank that can charge my laptop, but I don't know how to make it. The adapter input is 100v-220v~ 1.83A and the output is 19.7v ~3.87A Please, I really want to make it real and I think many people have the same idea, so I need your help.

Question by MirzhaK    |  last reply


Wiring Two Ports on a Phone Battery Bank in Parallel?

If a power bank claims that each port on it can charge a device at 2 amps, if I connect both ports together in parallel, am I able to get 4 amps? Or would it be just like trying to double the voltage off of the same battery, and not work? I have an Intel Compute Stick, which requires 3 amps to run. However, battery banks that provide more than 2.1 amps per port are super rare. Would it work to wire them in parallel?

Question by RocketPenguin    |  last reply


knex bank style safe

This is my new knex safe. it is called a bank styled because it looks like one and has an extreemly thick back wall made up of 5 layers of knex. yes i did just say 5 layers!!! however it does have some bad points, i made the mechinism to big and almost stops the door opening sou you have to push or pull it to get it open .second  it only has 16 combinations. third the door is easy to take of its hinges. fourth it has little room inside as the mechinism takes up a hell of alot of room.if you want instructions you can either heve istructions for this or saw the ride.

Topic by slithien    |  last reply


Wind Power Charge Regulators

Hello!! I need some help here...I am very "green" when it comes to alternative energy, so bear with me please! I recently decided to put together a small wind generation system to power my workshop. System is comprised of a 38v Ametek PMDC motor, 6.8' tri-blade array for propulsion. I also intend on installing a 2000 to 3000 watt modfied sine wave inverter powered by my battery bank to provide AC voltage to the shop. I want to be able to used the majority of the power created by my wind generator. I understand the concept of using a "shunt" but do not have a need for hot water or useless lighting. My question is this, would the Flexcharge NC25A charge controller (www.flexcharge.com/flexcharge_usa/products/nc25a/nc25a.htm) be sufficient enough to used in this system? Or is there something else out there that would maintain my battery bank without shunting the load when the bank is fully charged....Thanks in advance.

Topic by NMCBDet23    |  last reply


led powering question

I am building a garduino since planting season is coming near and this would be a great to start me seedlings off in. right now I have 3 banks of three red leds rated at 1.8v and in one of he instructible they said 7v was sufficient but i am connecting a 9v and can only power 2 leds and also I would like to go with an ac-dc converter but everyone i found has at least 800+ mA can someone point me toward a good power supply at the end I am looking at about 25 red and 8 blue LEDs

Topic by redwind    |  last reply


Help!! Hydro power

Hello! I need step by step instructions which shows how to build a hydro power system. I have to do this for a small hostel in the mountains. It needs to make 12v atleast and will use a alternator.I will need lots of help from you guys to build it all.Particulatly on the runner(what type for best efficiency,how to build it, cost, tools)and on the housing for the turbine(what material to use,it will have to be very durable and strong).I am an electronics expert so no need to explain to me what is what. Include a circuit which can charge a 12v battery bank . I am aware how a rectifier can be used to convert the alternator's AC to DC.I would like the rectifier circuit too.Added bonus if you show me how to make a housing for the turbine.Also I would like a homemade charge controller circuit too.The controller will have to have dump load options as well.If you can give a good way to water proof the whole thing... Kudos to you I will need all the plans for this project Alternator, Charge controller ,Blades, How to best wire battery bank etc. Please explain what materials to use etc. And please be aware this will be a rather low budget project.I prefer maximum efficiency and please do not worry yourself about where i will get flowing water etc.And please post your own pics if possible.It may not be possible for me to use power tools and a welder,I prefer simple tools, if not, no problem.

Topic by mhkabir    |  last reply


How many led lights can I power with 5v 2000mAh power bank?

I'm a guy who tries everything. Not an engineer or electrician but I would like to make a DIY camera light using LED strip and one or 2 5V powerbanks. Please advice on how to go about it.

Question by ShingaiG    |  last reply


Led powered by 9v

Hi all. I am new to this forum and need some help. I want to mount an led strip to the bottom of a roller skate. Everything I find already made up requires 12v. I need to keep the setup as small as possible for mounting reasons. How could I go about making a 12vdc led circuit work off a 9v battery or how could I wire up some led's on a flexible strip powered by a battery. I am thinking 9v because I can purchase a rechargeable set without draining the bank account each time. Any suggestions are welcomed. I have about 6" in length to mount the strip to. I would like multi color led but one solid color would also be fine. Thanks again for any suggestions.

Topic by rsfaze    |  last reply


Diy LED strip light powered from a solar powered battery bank (for painting/drawing at night)

I like to paint nightscapes and so far headlamps are not working so well for me. I used a portable light bar one night that worked well (on loan) but it was too heavy. I've been through stores looking for the right thing...and harbor freight came close. But I need something lighter weight and less expensive.  Two or three led lights don't cast enough light and 30 led storebought lights are too much light. I have a solar powered phone charger with battery bank (with usb connections) that I now plan to use as the portable power source. I plan to use a pringles potato chip tube as the light housing that can be attached by clips to my pochade (really a mod'd cigar box) on top of a camera tripod. I guess my main concern is weight on the box, so I thought running a cable off a power source hanging from the tripod would be more secure and less likely to fall in my palette (as has already happened). I need help figuring out the circuit board; and also choosing the right white led for color purposes. Any thoughts?

Topic by sreudianflip  


Electronics for power supplies

First, I apologize for being (almost) the hardware version of a "script-kiddie". I do want to learn the techniques involved but all of the electronics courses I've found work the wrong way around. They teach "this is what we have and this is what you can do with it" whereas my brain works in the "This is the problem, here is a solution and this is why it works." manner. This is how I learned software but when you get it wrong you can start again without losing the magic smoke! I have a 250ah, 12V battery bank, multiple DC devices requiring power and, eventually, several power sources for recharging. I also have several MC34063 chips and a few higher amp chips (somewhat optimistically as it turns out). Firstly, is there a practical course online that is built around this? Secondly (and probably extremely basic), if a device draws, for example, 3A is it self-limiting or do I need to put something between the source and the device too restrict the power?

Topic by ImmortalSoFar    |  last reply


POWERING SERVOS and other modules

Can you guys help me pls.I don't know how to power servos.My projects use an ultrasonic sensor with a few servos.when i try to power it up only 1 module that works.Can i power the servos using a different power source?like a power bank

Topic by Alexander heron the inventor    |  last reply


Would it be possible to put a power generating wind turbine on a car and store the power in a battery bank?

I'm trying to think of ways to store power in batteries so I can run household gadgets in my van without having to resort to a generator. 

Question by dcanimation    |  last reply


Supercapacitor for power supply design?

Hi I am new to electronics but I have studied the basics and the logic. I have 6 3000 farad supercapacitor from Maxwell(not the boost cap one) with a power rating of 3 watt- hour, so each capacitor holds about 10.8 kilo watts(3 watt x 3600 seconds= 10,800 watts). So I have been wanting to make a power supply out of these and two types have ran across my mind: 1. Turning them to a voltage multiplier type of circuit( so like a voltage multiplier but the capacitor is these capacitors). So I would have an output of 500 amperes(6 3000 farad capacitors in series would have a capacitance of 3000f/6=500f) and output voltage of 16.2 volts. For charging this power supply I will use a step down transformer connected to the mains with some circuit breaker, fuse, switch and ballast/ resistor at its input, the transformer will step it down to approximately 2 volts ac which then I will rectify with a bridge rectifier. 2. Putting them in parallel so I would have a total capacitance of 18,000 farad at 2.7 volts, and putting them in parallel with my power supply. So this works by charging the bank and the bank will discharge when fully charged. The power supply will be the same like the first design power supply. However this circuit seems very risky and I might need some feedbacks. For your information I live in Indonesia and the wall outlet have 220 volts with amperage of ~20 amperes So I have some questions which are: Q1. Which power supply design is more ideal in terms of safety and efficiency? And how can I improve? Q2. For power supply design 2, I believe I might need some "system" for timing the charge and discharge of the bank,what circuit or system should I use/ make? How about using relay? Or spark gap? Q3. What should I do to avoid explosion of capacitor in both power supply Q4. What components are recommended for the charging power supply and what diodes are recommended for the design one capacitor bank? I already have the thick wires necessary for this since i know both systems deliver huge amount of power. And please inform me if there is any mistake or anything wrong. Any input is very greatly appreciated, you don't meed to answer all question since i know is a lot and i don't want to waste anyone's precious time. Thank you so much for your time.

Question by dikap123    |  last reply


can I use AA battery bank to power an inverter (3000ma 12v)? Answered

Can I use AA battery bank to power an 50w inverter (3000ma 12v)?

Question by celalboz    |  last reply


Free power - is it feasible to get usable power from overhead HV wires ?

Is it possible to use induced power from below high voltage overhead cables ? - You can light a strip light tube from below them. Is it possible to utilise power from a receiver coil (or a bank of them) positioned underneath pylon cables ?

Question by and7barton    |  last reply


What's the best way to store pedal & solar power into a battery bank?

I'm looking to power some blenders & other small devices with a battery bank & I want to store power in these batteries from pedaling bicycles & possibly solar power. Just need a little help on all of the essentials and how much power I will be able to garner through a system like this. Thanks!

Question by nicksisson    |  last reply


Power banks and solar cells -could be great Instructable for you to make!

I was lucky to score a nice and real 8000mAh power pack with a solar cell from my local discounter.Realising the solar cell is more a gimmick than of real use I started to wonder....We all love our mobile devices and really hate that they need to be constantly charged up again.On long outdoor trips people used to carry a lot of gear and vital supplies.In todays times it almost seems that solar and battery power start to replace food and water.No trip is complete without pics, selfies and videos, some even take a drone with them.So: are there ways to increase your luggage weight by thinking smarter?Modern technology has come a long way and moves faster ever year.Solar cells are no exception here.Be it foldable setups or now even roll ups of flexible cell systems, you have the total freedom of coice.But then again: You are going on a week long camping trip in the middle of nowhere...Going on foot or using a bike means you need to keep the extras down or hire someone to carry them.Here are some of my yet to be finnished ideas:As long as you don't use them commercially feel free to make an Instructable or just use the ideas!1. Pop up amd normal tents.They seem to be the new standard now.Big with no poles on the inside and even someone who never used a tent can set them up.With the design comes a certain way of folding everything to pack it.Flexible solar cell designs won't break and can often be arranged so they would actually be able to replace parts of the outer tent material.And if it could mean they would get kinked too much and too often they are still perfect to create some "strap on panels" that can be rolled up and included with your foam underlay or mattress.A 200 or even 400W system can be transported easy and has less weight than a 80W fold up solution that you struggle to secure on your backpack or bike.2. Trackers!What is now almost a standard for fixed installations is still not seen in mobile setups.You pop up your panels, connect the power packs or batteries and go fishing, hiking or whatever.The sun moves on, the efficiency of the panels suffer.There are a lot of great Ibles for these solar trackers, from simple to 3 dimensional.Kites loves to use carbon fibre rods to reduce the weight.A tracking frame to hold a good sized flexible panel would count at less than 300 grams....In return you get up to 40% higher effiency and overall output compared to a fixed panel!Roll the panel up, fold the frame and you end up with a quite small roll that is easy to transport and very low in weight.3. Battery backups.No matter how long and well you planned, the weather might let you down shortly after your trip started.For a lot of comitted people that is no problem.The lack of power though can cause some to struggle to keep their video logs running.Your small drone might be great but it only lasts for less then 30 minutes until you need fresh batteries.Similar story if you use stabilizers, automatic tilt and pan gadgets or just a 360° camera.Just your cell phone alone can be a hassle if you use it as the main thing for GPS, pics and videos.At least one set of spare batteries seems to be a must have these days.For a lot of things it does make sense, for others not so much.Unless you really need ongoing power it might be enough to just charge you empty battery at the end of the day.But then the sun is down and options are gone for solar energy.In the RC area we can find a lot of powerful battery packs.Usually around 14V but 40 or more are no problem.And if you check the E-bike and scooter sections you will find some quite powerful and light weight battery packs.If you go outdoors a lot and for longer periods of time then it makes sense to replace the multiple battery options with just a single one.Use a high power backup battery with your solar system.DC-DC converters make it possible to literally combine everything with everything.Select the battery size so it will suit your charging needs and capabiliteis of the solar setup.Once time to close the tent you enjoy electricity to finnish your logs while your batteries are being charged during the night from the backup.4. Emergency generator.We all know these cheap gadgets like crank up torches or cranking mobile phone chargers.Nice to play with, utterly useless if you actually have to rely on them.A full charge for your modern phone might mean you crank for at least half the day - good luck!If you already carry a supply of gas for your cooking needs then these new fuel cells running on butane might be nice.Some of the Kickstarter projects actually made it into production!Prices though are more for real fans or those with enough money...But a small RC engine can drive some nice DC motor with very little fuel....In return you get a pocket sized generator that can charger your phone fully in the same amount of time a wall charger would...

Topic by Downunder35m  


Battery Powering an Rpi3 and Monitor?

So I have plans to assemble an Rpi3 laptop with a battery and display and all that. So I need a way to battery power my Pi. Could I power my Pi3 (5v@2.5a) a usb power bank (one that could provide 5v@2-2.5amps obviously) with perhaps a step down/set up regulator? But I still would need a way to power the screen. Most driver boards want 11-12v and I don't know how to provide that. Maybe wiring batteries in series or parallel? I'm not exactly sure on how that works but I'm new to LiPo's so I'd like some help please. Thanks!

Question by gupperino    |  last reply


Capacitor question?

I would like to know if I can hook up a capacitor to the incoming power being generated by my windmill so I can up my outage? I've been reading that you can use a capacitor bank to step it up. Thanks?

Question by swat420    |  last reply


What is the usual ratings for a capacitor in a disposable camera? Answered

I am wondering so that I can calculate the output power of my small capacitor bank-in amps and joules.

Question by wii552    |  last reply



AC motor power supply

I have an old Dayton electric motor I pulled out of a lab blower. (I have no idea how old it is, I pulled it out of my grandpa's bottomless basement.) It looks like it still works, but I found it with no wires or anything attached to the terminals. (All of the internal connections look good, however.) So, here's the tricky bit, how do I run power to it? I copied everything off of the label on the motor, and I'll post it on the end. I've got very near to 0$ in the project bank, so the cheapest I can possibly do this the better. I don't need anything nearly as sophisticated as speed control, or anything like that. Here's the info from the label: model: 5K261 HP: 1/3 RPM: 1725 V:`115 A: 5.4 Hz: 60 Time Rating: Cont. Temp. Rise: 48C PH: 1 Frame: 56 Brgs: Sleeve Code: H S.F: 1.35 S.F.A: 6.0 Amb: 40C No.: S60CXCDY-4065 Insul: Class: A Thermally Protected: AUTO I'm not quite sure what I'm going to do with it yet, that depends largely on how well it works.

Topic by Helioskannon    |  last reply


What is the right way to connect the cells of this battery pack, and tips on making a power bank? Answered

Greeting makers, I have a few questions about connecting Battery cells, and making a DIY Power Bank. And I'd like to hear your opinion on it. I have 12x Ni-Mh 1.2v 3000mAh AA betteries laying around. They are brand new and I thought of using them to make a Power Bank. Since most phones use 5v for charging I wanted to connect 4 cells in series giving me 5v and 3 of these packs in parallel for an end result of a single 5v 9000mAh Battery Pack. But when I started to connect them I realized that there are 2 ways it can be done, and I am not sure which is the right one. Is there any difference at all?  I will add a picture below, as it says more than thousand words. Furthermore I would like to ask for your opinion on how to proceed making a functional power bank. Just wiring the cells straight to an Usb port doesn't seem like a smart idea.  What would I need to make sure it is safe for the devices it charges? And how could I make the Power Bank rechargeable via Usb? Thanks in advance.

Question by icemaciop    |  last reply


What inverter should I use to tie in 3 60 watt panels into an outlet? Answered

I am trying to find a fairly cheap inverter to tie my panels into my home. I am planning to add a few more panels in the future. I am not going to add a battery bank. Thank you.

Question by pokey02    |  last reply


Can you use hydroelectric power for a water filter? Answered

 I'm surprised this hasn't come up before.. Hydroelectric power is great! could you use it to filter water into a jug on the bank?

Question by Houdinipeter    |  last reply


Is it possible to repair or repurpose a power bank charger where the mini connector to charge it has become dislodged?

I have an EYON power bank. A year after I got it, the mini connector broke off inside so I could not recharge it. I would like to either repair it or find a way to repurpose it to recharge it and then power/charge things but I don't know enough about how to safely open it without destroying it.

Question by blodefood    |  last reply


How to modify under-desk elliptical machine to charge portable power bank

Hi everyone, first post here!I have a Cubii under-desk elliptical machine which I use regularly at my desk job. I am thinking of modifying the machine so that it can charge an AC portable power bank (input 16.8V, 2.0A). Are there any projects or sources I can look at to see how this can be done? Thanks in advance!

Question by sky888    |  last reply



Powerful Pulse laser using capacitors.

Ok, i'm relatively new to electronics, but i've made a few projects and would like to try something more challenging. i've seen KipKays tutorials for making burning lasers and it got me thinking: instead of using a laser that's constantly on, why not charge up a medium bank of capacitors and use them to fire the laser for a micro second. surely this would mean that more power could be outputted while still powering it from a battery. there's probably something i don't undertand that would made this impractical, but i won't know until i ask. thanks in advance.

Question by DrVonTrap    |  last reply


No idea how to make this LED Windmill

OK, I have an idea that sounds kind cool but no working knowledge of electronics. How difficult would it be to make a bank of wind powered LEDS? A circut that progressively lights up more leds as the wind kicks up to a higher speed?

Topic by Eye Poker    |  last reply


Best way to light small bank of LEDs?

I was trying to help someone put together a small lighted prop for a Halloween costume, and quickly realized I knew enough just to be dangerous.  The result should be simple, for someone who better knows the intricacies: 9 superbright 3V LEDs, arranged in a circular pattern about 4in dia., powered by a small pack of batteries which CAN be located elsewhere on the costume, with a small wire run. Initially the thought was "oh, well, 2 AA's gets you the 3V, you're good..." Then we thought, "to make hooking up the LEDs simpler, attach them end to end, and then each end of the loop of LEDs goes to the two batteries."  Of course, totally wrong.  After realizing the glaring problem, it occured to us that 3 9V batteries would instead get us the requried voltage to light them up. Then, realizing again this should work but that there might be some finer points to know, I started looking up some information online for similar projects.  My big fears, having not tried this out yet, are that: 1) The string of LEDs or batteries may get hot. (Seen a lot of posts like this.) 2) There is some glaring inefficiency in this setup that could be more simply redone. For example, is it better or worse in any way to run three strings of 3?  Would batteries last longer if a different configuration of batteries or wiring were used? 

Question by dcenteno    |  last reply