---
title: UR@B Battery Pack
date: 2020-10-11
categories: projects school
excerpt: For a first try, not a terrible attempt at designing my own battery pack for UR@B. It did save quite a bit of money.
header:
  teaser: /assets/img/2020/batt_1.jpg

gallery:
  - image_path: /assets/img/2020/batt_3.jpg
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  - image_path: /assets/img/2020/batt_6.jpg
  - image_path: /assets/img/2020/batt_7.jpg
  - image_path: /assets/img/2020/batt_8.jpg
  - image_path: /assets/img/2020/batt_9.jpg
  - image_path: /assets/img/2020/batt_10.jpg
  - image_path: /assets/img/2020/batt_14.jpg
  - image_path: /assets/img/2020/batt_2.jpg
  - image_path: /assets/img/2020/batt_11.jpg
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  - image_path: /assets/img/2020/batt_15.jpg
  - image_path: /assets/img/2020/batt_16.jpg
  - image_path: /assets/img/2020/batt_17.jpg
  - image_path: /assets/img/2020/batt_1.jpg
---

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.

{% include gallery %}

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.