Tag Archives: DIY

Building my own 50Ah LiFePO4 lithium battery pack

via Dangerous Prototypes

Kenneth Finnegan posted his DIY 50Ah LiFePO4 lithium battery pack build:

Several years ago, I had purchased a 20Ah 12V Lithium Iron battery pack from Bioenno for my various 12VDC projects. To help protect it, I ultimately built it up into a 50cal ammo can with a dual panel-mount PowerPole connector on the outside, which has proven really nice as far as battery boxes go:
*20Ah is a decent battery capacity for a small load
*The packaged Bioenno pack left some space inside the box to also store the charger it came with, some PowerPole accessories, etc
*The fact that you’re able to close up the box and use the power connectors on the outside once you’re using it is real nice

More details on The life of Kenneth blog.

Low cost open source ventilator

via Dangerous Prototypes

Johnny Chung Lee writes, “In the event that COVID-19 hospitalizations exhaust the availability of FDA approved ventilators. I started documenting a a process of converting a low-cost CPAP (Continuous Positive Airway Pressure) blower into a rudimentary Ventilator that could help with breathing during an acute respiratory attack. If interested, follow along the Github Project

More details on Procrastineering blog.

DIY 18650 Powerwall with onboard BMS

via Dangerous Prototypes

A DIY 18650 Powerwall with onboard BMS @ openhardware.co.za

While I cannot afford a Tesla PowerWall, I’ve spent some time drawing up a PCB to house 7x 18650 cells in series. Each board has onboard Battery Management:
*Overvoltage Protection (per cell)
*Undervoltage Protection (per cell)
*Balance Charging
*Overcurrent Protection
*Main pack Fuse

The design files are available on GitHub.

Raspberry Pi Controlled DC Load

via Dangerous Prototypes

Dr. Scott M. Baker has published a new build:

In this video I build a DC Load that’s controlled by a raspberry pi. I’ve built dc loads before, but this time I decided to up the goal to supporting 100w (it actually handled 200w) using three mosfets instead of one. I drive it with a DAC and read back the actual state using an ADC. The CPU board is a raspberry pi, and I have a VFD, encoder, and some buttons for control. It also has a web UI.

Project info at smbaker.com.

Check out the video after the break.

Simple DIY active load

via Dangerous Prototypes

Charles Ouweland designed and built his own simple DIY active load, that is available on Github:

At first I was messing about with some big resistors but then I decided it would be nice to have an “active load” that you can set to a particular current. You can buy these things for quite some money but I decided to design and build myself a simple one using components and tools I have lying around. I decided to go analog, no digital stuff this time.

See the full post on Charles Ouweland’s blog.