With some few hacking, you can turn your old phone battery into a powerful Lithium battery pack. This is a great alternative for the expensive Lithium-Polymer battery packs. These things work well with Arduinos, DIY robots, speakers or any project that requires a high current power source.
What's The Secret?
The secret is simple. Obviously, phone batteries are designed to work with phones. A fail-safe circuit is added on top of the battery to prevent the battery from draining too quickly, overcharging and exploding. By removing the limiter, you'll be able to get full power out of those mobile batteries.
Why Upgrade To Lithium Batteries?
Lithium batteries are one of the most powerful batteries existing today. They are small in size, they have high charge capacities, and also have a high "c" rating. Lithium batteries are 6x-10x more power than AA (NiCd/ NiMH) batteries.
My Top 5 Project Application:
1st.) Robots & Drones
2nd.) Compact Speakers
3rd.) Arduino Projects
4th.) Compact DIY Gadgets
5th.) Solar Powered Reservoirs
Video Tutorial & Discussion:
I used the battery pack on last year's National Robotics Competition.
I was happy that I won 1st place in the championship with it! :D
Stay tuned! More Projects To Come!
I just got back from our vacation in the beautiful islands and beaches of Palawan :) I'll be posting a series of projects this month, including my: DIY CNC Build, Electricity Generating Footwear, 7 Homebrew Arduino Sensors, High-Precision Obstacle Robot and 10 other projects waiting in my draft list :)
WARNING: This is a dangerous project! There are risks in attempting the hack. I or site is neither liable if any of you gets injured. Don't forget to wear safety gears like eye-protection and gloves. Lithium batteries are prone to explosion. Before attempting the project, make sure you have enough experience over these batteries and don't forget to drain them.
Step 1: Finding Good Batteries
Here's the exact battery that I bought: MOBILE PHONE BATTERY (BL-5C 1000MAH)
Step 2: Peel and Remove the Label
Step 3: Clean the Battery
Step 4: Open a Small Gap
Don't worry, it's not what you think it is. The cover/ cap on top is actually a circuit and not the lithium battery's cover. The battery would not explode once removed, well not unless you short the Lithium battery.
Step 5: Remove the Limiter Circuit
Step 6: Insulate the Batteries
Step 7: Making Packs: Soldering Them in Series
You can increase the current by soldering the batteries in parallel. Soldering them in series makes the voltage much higher.
1 cell = 3.7v (1000mAh)
2 cells = 7.4v (1000mAh)
3 cells = 11.1v (1000mAh)
4 cells = 14.4v (1000mAh)
5 cells = 18.5v (1000mAh)