Battery Pack

Hello I am Saurabh, i recently made a design for battery pack. This design is a part of someone's project. This is not completely my project, but I was responsible for designing the battery pack case. I learned many new things during this process. This project helped me understand real design problems and how to solve them.

For this project, I was given a list of components to use. These included a 30×30×8 mm cooling fan, a 3.7V rechargeable LiPo battery, an adjustable step-down module, and a lithium battery BMS , LEDs and switch. All these components needed to fit properly inside the case. So, I had to design carefully according to their sizes.

Given are components links :

https://robu.in/product/5v-0-2a-3007-cooling-fan-for-3d-printer/

https://robu.in/product/dc-dc-xl4015-adjustable-stepdown-module-5a-75w-with-4-bits-digital-display-voltmeter/

https://electronicspices.com/product/3s-20a-12-6v-18650-li-ion-lithium-battery-protection-and-charger-bms-module-pack-of-1pcs

https://quartzcomponents.com/products/3-7v-10000mah-li-po-rechargeable-battery

First I made sketches of everything and how the box will look and add the measurements roughly. After making the sketches in the notebook I started making it into the Fusion 360 software. This are all the sketches that I make for this project. For every single design I made new sketch this help me to properly understand what I have to make .

After making the sketches, I first downloaded all the 3d models of the given components that are available. I downloaded the components from the Grabcad website i found fan, module, bms but not battery so i make a simple sketch as the dimensions of battery and extrude it . I am attaching the links of components which i found on Grabcad.

https://grabcad.com/library/hw-375-3s-20a-rev-2-3-1

https://s3.amazonaws.com/gc-p/cads/files/b1a25d2d956e9b023a372a223b138797/original.stp

https://s3.amazonaws.com/gc-p/cads/files/d8442cfd2bd1e253ead650bae8986d2a/original.step

I started by creating sketches in Fusion 360 and added all dimensions. In my first design, the fan was placed at the bottom, with the battery, module, and BMS above it. This design looked fine but had a major problem. The airflow was not proper, so heat could not be removed efficiently.

In the second design, I changed the placement of components. I moved the fan and module to the top, and kept the battery and BMS at the bottom. This improved the structure slightly. However, the fan and module were in the same line, so cooling was still not effective.

In the third design, I improved the airflow and arrangement. Most of the previous problems were solved in this version. The cooling was better, and the layout looked more practical. But only one battery could fit, which was not enough.

In the final design, I arranged the components in a better way. The fan was placed on the side, and the module was kept near it for better cooling. The BMS was placed at the bottom, and batteries were placed on the left side. This design allowed three batteries to fit and solved the airflow problem.After completing the main design, I added some extra features. I included a switch and four LEDs in the design. These additions made the project more useful and interactive. I also make sure they fit properly in the case

After printing the design, I found a mistake. I didn't make the U clip in the design, and the module was placed too low in the case. The module's display is at a very low point on the case, so we can't see it properly, and this could cause problems with fitting and usage. So, I corrected this issue in the final version.

These are all the dimensions and measurements I use to make the battery pack. I use tools like Fillet to make the design more beautiful, and I also make the design using the slot tool for the airflow of the fan.

After multiple designs and improvements, I completed the battery pack case successfully. I learned a lot from my mistakes and improved each version step by step. This project helped me understand the importance of testing and redesigning. It was a great learning experience for me.