Are you planning to build your own battery pack using 18650 cells but don’t know where to start? Worry no more! In this article, we’ll guide you through the process of wiring a 4s2p 18650 battery pack. Whether you’re an experienced DIYer or a newbie, this article is for you. So, let’s dive in!
What is a 4s2p 18650 Battery Pack?
Before we proceed to the wiring diagram, let’s first define what a 4s2p 18650 battery pack is. Simply put, it’s a configuration of 18650 cells that are connected in a series-parallel combination. 4s means that there are four cells connected in a series while 2p means that there are two sets of cells connected in parallel. The resulting voltage output is 14.8V (4 x 3.7V) while the capacity is doubled to achieve a longer runtime.
Why Use a 4s2p 18650 Battery Pack?
There are many reasons why you should use a 4s2p 18650 battery pack. First, it’s one of the most popular configurations for portable devices such as flashlights, e-bikes, and power banks since it provides a good balance between power output and runtime. Second, it’s relatively easy to assemble since it only involves a few cells and can be done without the need for sophisticated equipment. Lastly, it’s cost-effective since 18650 cells are widely available and can be obtained at a reasonable price.
Tools and Materials
Now that you know the basics of a 4s2p 18650 battery pack, let’s move on to the tools and materials that you’ll need to assemble it. Here’s a list:
| Tools | Materials |
|---|---|
| Soldering iron | 18650 cells (8 pcs.) |
| Soldering wire | Nickel strips (7 pcs.) |
| Wire cutter/stripper | Protection PCB (1 pc.) |
| Heat shrink tubing | Insulating tape |
| Multimeter |
Wiring Diagram
Now that you have all the materials and tools that you need, it’s time to proceed to the wiring diagram. Follow these steps:
Step 1: Prepare the Cells
Take eight 18650 cells and ensure that they’re charged to the same voltage level. Then, wrap each cell with insulating tape to prevent short circuits. Next, use a wire cutter/stripper to remove the insulation from both ends of each nickel strip. Lastly, apply some heat shrink tubing on each strip to provide protection.
Step 2: Connect in Parallel
Take two cells and connect them in parallel using a nickel strip. Repeat the process for the other two cells. This will give you two sets of cells connected in parallel.
Step 3: Connect in Series
Take each set of cells and connect them in series using a nickel strip. This will give you two sets of cells connected in series. Make sure to observe the correct polarity (+ and -) when connecting the cells.
Step 4: Connect Both Sets
Take one set of cells and connect it to the other set of cells in parallel using a nickel strip. This will give you a 4s2p configuration. Again, observe the correct polarity when connecting the cells.
Step 5: Install the Protection PCB
Connect the protection PCB to the battery pack to protect it from overcharging and over-discharging. Make sure to observe the correct polarity when connecting the PCB.
Step 6: Test the Voltage
Use a multimeter to test the voltage output of the battery pack. It should read around 14.8V. If the voltage is lower, charge the battery pack until it reaches the correct voltage level.
FAQs
1. How many cells do I need for a 4s2p configuration?
You need eight 18650 cells to achieve a 4s2p configuration.
2. Can I use other types of cells aside from 18650?
No, you should only use 18650 cells since they’re the most suitable for this configuration. Using other types of cells may result in compatibility issues and safety hazards.
3. Can I skip the protection PCB?
No, the protection PCB is essential to prevent overcharging and over-discharging, which can damage the battery pack or even cause a fire or explosion.
4. How long will the battery pack last?
The runtime of the battery pack depends on the capacity of the cells and the power consumption of the device. Generally, a 4s2p 18650 battery pack can last up to several hours or even days depending on these factors.
5. Is it safe to assemble a battery pack myself?
Assembling a battery pack can be safe as long as you follow proper safety precautions and use the right tools and materials. However, if you’re not confident in your skills or knowledge, it’s best to seek the help of a professional.
That’s it! You now have a 4s2p 18650 battery pack that you can use for your DIY projects. Always remember to handle it with care and avoid exposing it to extreme temperatures or physical stress to ensure its longevity and safety. Good luck!
