UR@B Battery Pack

Note Autonomous Underwater Vehicles at Berkeley (AUVs) has been renamed Underwater Robotics at Berkeley (UR@B). Does this cause confusion? Yes. Did we do it to better reflect the changing goals of the team? Yes.

Way back in March after heading home because of the pandemic, I immediately got to work on my projects. After doing power requirement planning to specify a battery for the Robosub, I realized that the Blue Robotics battery is just about right. However, it costs $300. As far as considering development costs go, it’s perfectly worth it, but given we are a new team with little funding (@Berkeley pls give us more funding) I decided to go the DIY route which ended up having more capacity and only cost $120.

Incoming collage of assembly pics. Man this thing took quite awhile to build.

At the end of the day I had to ask myself several questions. Is it a 4S7P 21Ah Li-ion battery pack? Yes. Was it worth it? Sure. Should I have used a better spot welder? Definitely. Should I have used nickel strips with the right thickness and width for the current I want to push? Again yes. Is it stiff enough? Nope. Would heatshrinking the whole battery improve that? Yup. Would I rely on this battery for competition? Absolutely not. Is the team going to buy a new Blue Robotics battery instead? Yes thankfully we have a little more funding this semester. Can this be used as backup? Yeah batteries are expensive. Does it look like a stick of dynamite? Why yes it does.