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.
November 18, 2019 at 10:08 pm
Comparing quotes to get the cheapest possible insurance – Be sure to shop for car insurance quotes just after the three- and
June 8, 2021 at 1:50 am
thanks
November 18, 2019 at 10:10 pm
Get A Co-signer. If you walk into a bank or in the office of a lender by yourself, with no credit history and no guarantor to vouch for the fact that you are actually .
November 18, 2019 at 11:24 pm
To help you better understand it, here are a few things you need to know about the “I’m Feeling Curious” Google trick.
November 19, 2019 at 1:00 am
Are you Looking for Buy Indian Lehenga Choli Online Shopping ? We have Largest & latest Collection of Designer Indian Lehenga Choli which is available now at Best Discounted Prices.
November 19, 2019 at 6:32 am
thanks for sharing https://escortserviceshyderabad.in/
November 21, 2019 at 7:25 am
Ahmedabad Escort service
November 23, 2019 at 2:24 pm
NEET Rank Predictor is the best tool to predict the ranks before the declaration of results. The NEET Rank Prediction tools 2018 helps the candidates to select the preferred choices in medical and dental colleges as it provides help in the calculation of the probable rank.
November 25, 2019 at 1:15 am
This is a great invention for me, I have to work on my computer for a long time and I could not charge my phone battery, this USB will help me
November 25, 2019 at 1:52 am
That was the best advice ever. Indeed if you need Online Assignment Help, these guys are just the best.
November 26, 2019 at 12:33 am
Webroot delivers next-generation endpoint security and threat intelligence services to protect businesses and individuals in a connected world. Manage your security across multiple devices, with any Webroot product. Smarter protection that stops threats in real-time to secure businesses and individuals wherever they connect. Download and Install Webroot security on your computer.
November 26, 2019 at 8:12 pm
Juul Australia
November 26, 2019 at 10:46 pm
Uno Assignment Help is the best online assignment help to students pursuing courses in school colleges and universities of USA, Australia, UK, Canada and New Zealand. Our in-house experts provide best quality homework help. If you strive for individual attention and customized help in any assignment, homework, coursework, essay, term paper or research work and report writing; our team of talented experts is here to assist you with high quality solution. Whether it is an urgent assignment help, homework help, online tutoring we ensure reasonable price and timely delivery of every order you place with us
November 27, 2019 at 1:20 am
Students often look for the services that offer all kinds of assignment help online to avoid any knowledge gap in assignments.
November 28, 2019 at 2:21 am
Nice Post I will Come Back Again
November 28, 2019 at 3:00 am
Thanks for your guidance !
November 29, 2019 at 12:16 am
I am the first time hearing your tips to charge the battery by a phone charger. I will surely buy this USB ..
theacademicpapers
November 29, 2019 at 7:55 am
Indeed this is true, especially when you need to review a movie. You may need Movie Assignment Help to get a customized paper.
December 3, 2019 at 5:18 am
At Mumbai escort agency you will get justified values which can make deepest association with our services. In all means of trustworthiness, we can make you assure that you would be pretty happy when your session ends up with a magnificent experience with our girl.
https://mumbaipersonals.com/
December 3, 2019 at 5:48 am
They provide highly customized and quality content that is free of any sort of plagiarism and errors. We have helped thousands of students in the 10 years of our operations and they all have been able to score the best grades.
December 3, 2019 at 5:50 am
They provide highly customized and quality content that is free of any sort of plagiarism and errors. We have helped thousands of students in the 10 years of our operations and they all have been able to score the best grades.
assignment help online
December 4, 2019 at 3:31 am
MyAssignmentHelp provides its customers with the widest subject coverage. At MyAssignmentHelp, our professional writers are proficient in over 100 subjects for assignment writing, essay writing, research papers, coursework and dissertations and projects.
December 4, 2019 at 5:37 am
Excellent blog…..Great content….
December 4, 2019 at 7:01 am
The Hyderabad Call girl is a perfect choice. Call girls are gorgeous, beautiful outlooks, offering flawless pleasing attitude with desire. They understand professional to keep the outlooks to look stylish with the gaze of clients.
December 4, 2019 at 7:02 am
thanks for sharing
December 4, 2019 at 7:02 am
thanks
December 5, 2019 at 6:44 am
Really Great Post!!! Thank you, Admin, for Sharing your post.
December 5, 2019 at 6:45 am
Really Great Post!!! Thank you A lot, Admin, for Sharing your fantastic post.
December 7, 2019 at 1:44 am
I recommend that everyone should seek assistance from Assignment Help Australia for the best academic help. There are professional experts from various esteemed universities in almost every field. They are capable to write the premium quality of assignments according to the requirements of students and university norms.
December 7, 2019 at 4:19 pm
Really Amazing Post!!! Thank you A lot, Admin, for Sharing your fantastic post.
December 9, 2019 at 12:11 am
hulu.com/activate is the cheapest online video streaming services grown ever more popular, cable connections or subscriptions became un popular and peoples are looking to cut the cord with cable operator and switching to Hulu simply activating by visiting
https://www.go-hulu.com/
December 9, 2019 at 5:55 am
thank for sharing
December 9, 2019 at 5:56 am
Thank
December 10, 2019 at 6:27 am
Hi, I only want to say incredible article. You have explained everything very well. Our dissertation helpers are well-versed with all the academic topics and always giving great writing for the students. Dissertation providers deliver law dissertation help. We also provide a history dissertation help. Great work Keep it up!
December 10, 2019 at 6:35 am
Hi, I only want to say incredible article. You have explained everything very well. Our dissertation helpers are well-versed with all the academic topics and always giving great writing for the students. Dissertation providers deliver law dissertation help. We also provide history dissertation help. Great work Keep it up!
December 10, 2019 at 1:31 pm
Thanks for the post. Indeed the Fire brief AssignmentHelp is readily available if you need it.
December 11, 2019 at 6:22 am
Our online assignment help is the most trusted among students from all universities across Australia. At myassignmenthelp, we suggest you to relax more and concentrate on other important tasks and trust us to avail the best online assignments help.
December 11, 2019 at 11:21 pm
wendy’s restaurant is now offering free food coupons and exciting prices worth up to 500$. Register here: talktowendys
December 13, 2019 at 11:11 am
Thanks for the great post. If your computer printer says the printer is offline? Then it means, your operating system doesn’t have a connection via your router or other wi-fi connection. Actually, WI-FI connection is a bridge or you can say a bypass that keeps your printer in a live mood but as you lose your connection.
December 13, 2019 at 11:12 am
Thanks for sharing the great post. Let’s check out how you can resolve it if you are having internal issues to get printer is offline to online. If you have internal issues it may be a cause of a wireless network. Sometimes, network issues show the fault or you can say the error of printer offline cause of the wireless connection.
December 16, 2019 at 6:19 am
Thanks for sharing the useful info.
want to use automotive invoice software
December 16, 2019 at 6:19 am
Thanks for sharing the useful info.
want to use automotive invoice software
December 16, 2019 at 10:52 pm
This is customary progress since it is amazingly important that our telephone looses its charge quickly by righteousness of our utilization.assignment helps
December 16, 2019 at 10:53 pm
Extremely Great Information you shared through this Article. Much obliged to you for sharing your post.assignment helps
December 17, 2019 at 3:24 am
Allassignmenthelp.com is the best solution that wants homework writing service and online assignment help.
December 17, 2019 at 11:52 pm
Gone are the days when you needed to ask your companions for task composing help. Be that as it may, presently you don’t have to stress when you have task help on web. Our scholars guarantee convenient correspondence with the customers to satisfy their predefined rules to a tee. To get the best help with the UK, visit our site now.assignment helps
December 18, 2019 at 7:16 am
That will be revoltionary. Great appreciated work by you. Thanks a ton ! :)
October 9, 2020 at 8:17 am
It’s good idea for Battery-powered USB Phone Charger. I think it is very useful when traveling. POS System Maker & Supplier
December 18, 2019 at 12:02 pm
Throughout the term, students will use this site to host public online discussions of key topics in the course.Condominio Santa Ana Village
December 18, 2019 at 12:06 pm
Hi, Throughout the term, students will use this site to host public online discussions of key topics in the course.Condominio Santa Ana Village
December 19, 2019 at 6:16 am
UK dissertation Help is one of the most sought-after dissertation writing help in the UK that has been helping students for years and offers the most gratifying services. So, do not let the toughest project of your course disappoint you. Experts know the best. Get in touch today!
December 19, 2019 at 12:01 pm
Top Selling Best Amazon Alexa Echo Smart Speaker – Amazon added an LED clock to its third-gen smart speaker to create the Echo Dot with Clock, and it’s our favorite speaker for the price. Not only does this 2019 third-gen Dot boast impressive sound for its modest profile. The third-generation Amazon Echo speaker, released in October 2019, is one of most premium Alexa the one most people should think of buying when they consider an Alexa voice-controlled speaker, and it’s the best Alexa speaker for those who are new to smart speakers.
March 19, 2020 at 5:30 am
Thanx for the really great news .
February 21, 2024 at 12:06 am
Thank you for sharing this informative blog post.
Helping students tackle their Computer Network Assignment Help can be tricky. That is where My Assignment Help comes in. We offer expert assistance with assignments covering computer networking fundamentals like the OSI model, TCP/IP protocol stack, network routing and switching, network security and more. Whether you need help with a homework, lab or project, the computer networking specialists at My Assignment Help deliver tailored guidance that zeros in on your specific needs and teaches important concepts along the way. Their patient tutors ensure students understand the material while completing assignments on time to avoid stress and earn better grades.
https://globalassignmentexpert.com/computer-network-assignment