I was getting ready for a long train ride from KY to DC and found out there aren’t any AC outlets for coach seats! A 15hr ride isn’t too bad when you have a smart-phone; then again, the stock battery on an HTC Incredible will last only about 3hrs of heavy usage. Not good. I wanted a way to be able to use it for, well, 15hrs. So, using some easy-to-find parts I made an extended battery that will charge the phone via USB. I also wanted the extended battery to be rechargeable. So, I need to be able to have access to the battery contacts; maybe later I will add something fancier, but for now the battery disconnects from the USB circuitry. Here’s my finished product, and how to make it.
I bought a battery from the local Home Depot for $20 (look in the outdoor lighting aisle). It is 6V and provides 6.5AH. You can get it cheaper at places like batterymart.com, but I was in a hurry and the shipping on seal-lead acid batteries is not cheap. The higher the amp-hours (6.5AH in this case), the longer you will be able to run your USB device.
Now for the voltage – USB uses 5V DC. I needed to drop the voltage from 6V to 5V, preferably without too much loss. There are three main options: voltage divider using resistors, non-switching regulator, and a switching regulator. In the case of the voltage divider, the resistors basically turn the extra voltage into heat, and they would need to be rated for higher power than the typical $0.01 resistors. Switching regulators, or DC-to-DC converters, are much higher efficiency, but are more costly. Also, I couldn’t find one that would work at Radio Shack, so I went with a non-switching regulator: the 7805.
The 7805 regulator will take voltages higher than 5V and hold them at 5V, also allowing up to 1A of current. While that’s much more than is needed, it gives a nice buffer. A regulator has three legs: 1) input, 2) ground, and 3) output, where the ground leg is shared between the input and output. The input comes from the positive side of the battery, the output goes to the 5V pin on a USB connector, and the negative side of the battery along with the GND pin on a USB connector both connect to the ground. Since the 7805 drops the difference in voltage by heat, adding a heatsink to the regulator might be needed, depending on how much power your device will draw.
To connect USB devices, I need an adapter that would allow me to plug in a standard USB cable, like the one in your computer. I happened to have an old PS2/USB adapter from an old mouse. It hasn’t been used, ever, so I cut it up (the green thing above). You could use something else, like a USB extension cable which already has wires to solder to. USB connectors have 4 pins: 1) 5V, 2) Data+, 3) Data-, and 4) GND. Use some wire to solder the connections (USB 5V -> 7805 Output), (USB GND and Battery negative -> 7805 Ground), and (Battery positive -> 7805 Input). Make sure to protect the solder points with some heatshrink or risk shorting, melting, and other bad things. To connect the wires to the battery terminals, I used spade connectors. Also, leave the terminals pointing up for reasons I’ll point out soon.
Once the soldering is done, connect the battery and use a multimeter to check the output on the USB connector (voltage across pin 1 and pin 4 should be +5VDC). Then you can freely connect a USB device and you’re set. You could stop here and be done. Since I wanted this for travel and didn’t want exposed wires, I took it a step further: enter hot glue.
Clean the top of the battery and add a layer of lubricant (e.g. WD-40) to keep the glue from sticking to the battery. We want the circuitry to be detachable so that we can recharge the 6V battery using a trickle charger/car charger. This is why I left the battery terminals sticking up – so that I can freely pull the circuit away from the battery. I used about 10 – 15 sticks of hot glue used on a mini gun, just to make sure that everything would hold together. This is the most time-consuming part. It doesn’t take a lot of thought to do this. Just fill in all the holes, keeping the USB port accessible. You also want to keep the heatsink partially uncovered so that it passing air can pull away the heat given off by the 7805 regulator. You could spend a lot of time getting this pretty by squaring up the sides and making it colored, but this was a last minute project for me. Hopefully you will get some good use out of this – I know I will. I hope they don’t kick me off the train thinking it’s a bomb.
March 15, 2021 at 6:18 am
Looking from a wide pack of blenders for smoothies was not a fundamental assignment. Notwithstanding, we set forth a reasonable endeavor to direct you toward purchasing the best blender for smoothie bowls.
March 16, 2021 at 12:08 am
Geetanjali Test Tube Baby Center in Hyderabad is an embodiment of the mythical stork that delivers bundles of joy.
test tube baby hospital in hyderabad
March 16, 2021 at 12:11 am
Geetanjali Test Tube Baby Center in Hyderabad is an embodiment of the mythical stork that delivers bundles of joy.
March 16, 2021 at 5:02 am
Have you recently gotten new Brother printer? And you don’t know how to connect brother printer to computer Furthermore, you’d prefer to attach it to your work area or PC? At that point, on the off chance that you have the vital abilities, you can undoubtedly associate it. Furthermore, in the event that you are not a specialist and considering how to interface Brother printer to PC, at that point don’t stress! This guide will help you all through the way toward interfacing both the gadgets. If your issue nor resolve this you can also call us we provide you to 24/7 customer help just call on this 1-844-273-6540
March 16, 2021 at 6:46 am
so nice blog i like it so much thanks to sharing this informative blog with us.
May 6, 2021 at 10:57 am
If you are thinking of avail the best assignment help Adelaide service at a reasonable price that comes with great quality too?” at that point, put your query here and get the best solution as per your need and requirement.
May 6, 2021 at 11:07 pm
IoT Cybersecurity Services
May 6, 2021 at 11:09 pm
IoT Cybersecurity ServicesIoT Cybersecurity ServicesIoT Cybersecurity ServicesIoT Cybersecurity ServicesIoT Cybersecurity Services
May 7, 2021 at 3:44 am
Great content & thanks for sharing! I’m a content writer and recently I have written a GeneratePress theme review.
May 7, 2021 at 5:22 am
Antes de tirar as cartas do tarot “Sim Não”, você deve pensar em uma questão específica.A tiragem “Sim Não” te convida a tirar 6 cartas a partir das quais estudaremos os elementos favoráveis que possibilitem visualizar uma resposta positiva e, por outro lado, os obstáculos que deverão ser considerados para o futuro.
May 7, 2021 at 9:15 am
Well written post with lots of information. Do share more like this. So I also recommend you to visit Non alcoholic fatty liver disease for reading More.
May 7, 2021 at 9:18 am
Pretty good post. I have just stumbled upon your blog and enjoyed reading your blog posts very much. I am looking for new posts to get more precious info. Big thanks for the useful info. nonalcoholic steatohepatitis
May 7, 2021 at 9:19 am
Pretty good post. I have just stumbled upon your blog and enjoyed reading your blog posts very much. I am looking for new posts to get more precious info. Big thanks for the useful info. nonalcoholic steatohepatitis
May 10, 2021 at 9:19 am
I hope you will have more blogs or more articles to bring to readers. You are doing a very good job!
May 10, 2021 at 9:20 am
I am really very happy to visit your blog. Now I am found what I actually want. I check your blog every day and try to learn something from your blog. Thank you and waiting for your new post.
May 10, 2021 at 9:21 am
I am really very happy to visit your blog. Now I am found what I actually want. I check your blog every day and try to learn something from your blog. Thank you and waiting for your new post.Kite
May 17, 2021 at 1:39 am
This is definitely useful information if you want to keep your contacts updated and organized. Thank you!Excellent article. The writing style which you have used in this article is very good and it made the article of better quality.
May 18, 2021 at 5:46 am
I usually play with low competitive keywords for fast ranking. However, some of my blog articles are targeted at very competitive keywords in my niche.
May 18, 2021 at 5:47 am
If a new website start using highly competitive keywords in their niche of their business then there are fewer chances of quick result and at the same time if a smart keyword research decision is made by using good search and medium or low competitive keywords then maximum benefit can be achieved in fewer months if the content is genuine and informative.
May 18, 2021 at 5:47 am
if a smart keyword research decision is made by using good search and medium or low competitive keywords then maximum benefit can be achieved in fewer months if the content is genuine and informative.
May 19, 2021 at 8:03 am
At one place get all your needs. Know which are the upcoming web series release in India, which memes are going viral currently in India.
May 20, 2021 at 12:20 am
High quality economic Assignment Help at highly competitive rates. Get microeconomics assignments prepared by highly qualified professionals and score high grades on all your assignments.
May 20, 2021 at 5:28 am
Nice post. it is very interesting and informative. Thank you for the sharing.
May 21, 2021 at 2:11 am
Hi, I am Cristina Parker from USA. I am a writer associated with acadecraft.com. We provide Taxonomy, Content Designing, Online Cataloguing, and other multiple services. If you have less time to completing your tasks, you’re welcome to acadecraft.com.
May 22, 2021 at 6:22 am
Academic essays are a common thing at colleges and universities. Students often get tired of writing academics essays on different subjects. If you are no longer willing to do so, you can avail top-quality essay academic help from my assignment experts.
May 23, 2021 at 2:05 am
Set up your printer
123.hp.com/setup
You can print from your Chromebook using most printers that connect to Wi-Fi or a wired network. Currently, Chromebooks don’t support Bluetooth printing.
Tips:
You can connect your printer to your Chromebook with a USB cable. When you use a cable, a notification appears. Follow any on-screen instructions. When your printer is connected to your Chromebook, it doesn’t need to be connected to Wi-Fi.
May 23, 2021 at 2:09 am
Set up your printer
123.hp.com/setup
If the printer is covered by the warranty, the support service may be available for free from the manufacturer. We disclaim any ownership in, right to, affiliation with, or endorsement by unless stated. Users are advised to review our policies before using the HP Printer.
To visit: 123.hp.com/setup
Catch ahold of @ 1-819-716-0730
May 23, 2021 at 2:11 am
Set up your printer
If the printer is covered by the warranty, the support service may be available for free from the manufacturer. We disclaim any ownership in, right to, affiliation with, or endorsement by unless stated. Users are advised to review our policies before using the HP Printer.
To visit: 123.hp.com/setup
Catch ahold of @ 1-819-716-0730
May 24, 2021 at 12:19 am
Hello guys. Have you seen a new article on https://elitewritings.com/cover-letter-services.html The service is reliable and helps students gain academic success. See the popular educational posts there.
May 24, 2021 at 11:36 pm
New Online Assignment help online writing service is the best solution for that student who says HND Assignment Help Our team of experts knows university guideline and completes the assignment on the desired deadline. By using these online Assignment help student scores well because of the qualitative assignment. We provide students 24 hours of customer support so they can reach us at any time.
https://www.newassignmenthelp.co.uk/hnd-assignment-help
May 24, 2021 at 11:37 pm
What a nice blog! I have enjoyed reading through the article. Nice Informative Post. Keep Updating more things for us.
https://www.newassignmenthelp.co.uk/hnd-assignment-help
May 24, 2021 at 11:38 pm
Thanks for sharing……
https://www.newassignmenthelp.co.uk/hnd-assignment-help
May 24, 2021 at 11:38 pm
Thanks for sharing……
May 25, 2021 at 1:55 am
The English assignment writer for our organization is a top-class and skilled person. Our master writers realize how to compose school and college assignments. Our English assignment writer will give you complete academic fulfillment. Like some other language, English likewise has its a lot of issues. Students as a rule deal with issues like artistic investigation and tight cutoff times. In this manner, our writer is fit for eliminating every one of your concerns by writing the best substance for you. You won’t ever need to deal with the issues of late entries too.
May 26, 2021 at 5:26 am
Good blog,
Hotels in Chennai, Budget Hotels in Chennai, Hotels in Chennai near US Consulate, Hotels in Chennai near Apollo Hospitals, Hotels in Chennai near Central Railway Station, Hotels in Chennai near Sankara Nethralaya, Hotels in Chennai near Marina Beach, Hotels in Chennai near Egmore Station, Best Hotels in Chennai, Top 10 Hotels in Chennai, No:1 Hotels in Chennai, Affordable Hotels in Chennai, Economic Hotels in Chennai
https://www.mallikaresidency.com
May 26, 2021 at 9:21 am
Such devices are quite difficult to find on the market, so your article is quite relevant. I also sometimes publish unique material and run an author’s blog. Now I also study in college to successfully combine hobbies and student commitments I am helped by the best professionals https://essaysservice.com
May 26, 2021 at 1:33 pm
I am developing a website for crypto traders. Here https://safetrading.today/traders/free/ you can find the best telegram channels with crypto signals.
May 26, 2021 at 10:33 pm
Place your order at ABC assignment help and access the writing skills of best Australian academic writers. You can meet the due dates of your project submission even if you have less time to write your papers using our online writing services.
May 27, 2021 at 1:54 am
Global Translation Help is a USA-based translation company that provides Academic Document Translation Services all over the world. We have a large team of ATA-certified translators who are able to provide international students with a certified letter accompanying each of our translations. Our specialist academic translators have years of experience translating academic documents, such as assignments, case studies, and many others in more than 200 languages. To get the best academic translation services, don’t think twice and contact us.
May 27, 2021 at 10:35 pm
Great Blog. Really Nice and Informative, keep it up !
what is future of web development
May 28, 2021 at 4:53 am
There are some interesting points in time in this article however
I don’t know if I see all of them heart to heart. There’s some validity but
I will take maintain opinion till I look into it further.
If you want to know about Harvard Outline, We are having a team of experienced writers who can help you out.
May 29, 2021 at 12:21 am
Great Blog. Really Nice and Informative, keep it up !
computer networks interview questions
May 29, 2021 at 1:21 am
IT is a lucrative field and hence many students flock to study this subject. However, once into the studies, students realize that it isn’t just about the studies but also about everything else related to the academic institute. If you are a student of IT and in need of customized and top notch Programming Assignment Help, then get in touch with our experts at Help in Homework and score as per your desire. Our experts will meticulously complete your assignment on time and at an unbelievably reduced cost and will ensure you a smooth academic life and a path to a better future.
May 31, 2021 at 12:56 am
We are no 1 assignment writing service provider in the world and especially in Australia. Please connect with us: Phone: +61-2 9191 7405, E-mail: sales@no1assignmenthelp.com, Website: assignment help, Office: Level 4/22 Harry Chan Avenue, Darwin City NT 0800, Australia
May 31, 2021 at 1:50 am
Mari bergabung bersama pokermilan,pertanyaan adalah kenapa harus bergabung dengan pokermilan?
-kami memiliki banyak metode pembayaran melalui antarbank,deposit pulsa, dan dompet digital
-kemenangan berapapun akan di bayar
-proses setor tarik yang begitu cepat
-customer service professional dan ramah yang akan selalu membantu anda
-promo dan bonus yang sangat menarik
-keamanan data yang sangat terjamin
Segera daftarkan diri anda di situs pokermilan, segera daftar di situs agen poker online
June 1, 2021 at 3:32 am
Global Translation Help is a USA-based translation company that provides Academic Document Translation Services all over the world. We have a large team of ATA-certified translators who are able to provide international students with a certified letter accompanying each of our translations. Our specialist academic translators have years of experience translating academic documents, such as assignments, case studies, and many others in more than 200 languages. To get the best academic translation services, don’t think twice and contact us.
June 2, 2021 at 8:53 am
That means washing hands regularly and thoroughly. You might want to consider putting hand sanitiser in bathrooms, meeting rooms and other commonly used areas, and ask staff to wipe down shared equipment like phones or laptops after every use.
June 2, 2021 at 11:19 am
This is really wonderful record!
June 3, 2021 at 1:43 am
Thanks for sharing these impeccable tips and I will definitely be going to try them all if ever I publish my novel anytime
June 3, 2021 at 1:44 am
It’s a post where I can find really useful information for myself.