Video · DIY Builds & Mods
DIY Waterproof 12V Battery Box for Fish Finder and Livewell
I build a waterproof 12V battery box that powers my fish finder, livewell and lighting on the kayak, using a watertight container and simple parts.
What’s in this video
I needed one clean way to power my kayak gear, so I built a waterproof 12V battery box. It starts with a large watertight container. A stainless PG7 cable gland lets the wire out, and inside I used SAE connectors, a 4-way SAE splitter and an on/off toggle switch. F2 crimp-on connectors go on the battery terminals. An in-line fuse is optional, but some fish finders need a specific amp rating.
I went with a 12V 9ah UPG battery. It is the same size as many 7 and 8ah batteries, it just weighs more, and the case can hold a bigger battery if you need one. I covered my splices with heat shrink tubing because it makes a rounded cover that seals well when it passes through the cable gland.
Quick takeaways
- A 12V 9ah battery fits the same footprint as many 7 and 8ah batteries, it just weighs a bit more.
- Heat shrink on your splices seals better through a cable gland than bare tape.
- Check whether your fish finder needs a specific amp rated in-line fuse.
- Compare the container and battery dimensions before you buy if you go bigger than 9ah.
Gear from this video
- Watertight Container (Large Size)
- SS PG7 Cable Gland (x1)
- SAE Connectors (x2)
- On/Off Toggle Switch (x1)
- Battery 12v (we used 9ah by UPG) (x1)
- Amzn.to
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