Built from scratch
I wanted to build something from scratch that would challenged everything I've learned so far on this journey. I've read several books & blogs, watch numerous YouTube videos, and most importantly, conversed with those who have a lot of experience.
I was at Harbor Freight one Saturday and they had a sale on these small ammo boxes. I thought it would be perfect for what I had in mind.
Project goals
I wanted to construct something that was...
- Less then $300 USD
- Portable
- Low voltage (12v)
- 10Ah or greater battery
- Solid state (no moving parts)
- Water resistant
- Safe (so I wouldn't electrocute myself, blow anything up, catch on fire, etc.)
- Last but no least, useful and cool
Prototype 1
Take aways from this prototype:
- Charge controllers need to be high quality. The one pictured was junk. Several quality issues (terrible soldering on controller board, inconsistent battery level readings, positive grounding, the list goes on and on).
- Lid needed to opened for charging. I thought this wouldn't be a big deal, but it really bothered me. I wanted to see if there was a way to make work and I found a great solution that I'll share in the next prototype.
- No breakers/fuses is asking for trouble and violates one of my goals, safety.
- Bolts sticking out of the side of case. Not acceptable.
- No rubber gaskets on bolts. High risk if the unit gets wet.
Next steps
I'm working on my final prototype and will do a full write up once it's complete. There's several improvements and I'm happy with the results. I plan on sharing a lot of the details including several YouTube videos.