DIY Off Grid Battery Pack From EV Battery

A man's hand with a black ring touches a white box. It is square on the bottom and has a sloped top. Various AC, 12V, and USB ports adorn its surface. It's approximately the size of a human head.

Car camping gets you out in the great outdoors, but sometimes it’s nice to bring a few comforts from home. [Ed’s Garage] has taken a module from a salvaged EV and turned it into a handy portable power station.

With 2.3 kWh of storage from the single Spark EV module, the battery pack can power [Ed]’s hotplate, lights, fridge, and other electric accessories while camping away from shore power. The inverter he selected can provide up to 1500W of AC power and his 12V converter can do 150W. Several USB ports and a wireless charging pad adorn the outside next to the waterproof AC ports. He even printed a small magnetic flashlight to reuse the light from the inverter which uses an 18650 cell that can be charged from the big battery in a charger built into the exterior of the pack.

The battery management system (BMS) has a Bluetooth module allowing for remote monitoring of state of charge and setting the maximum and minimum charge points for the pack. The whole thing comes in at 73 pounds (33 kg), and while he had originally thought to give it wheels to roll, he changed his mind once he thought more about what sort of wheels he’d need to maneuver the thing in the backcountry.

If you’re thinking of building your own power pack, why not checkout a few other builds for inspiration like this one from tool batteries or one designed to charge directly from a solar panel. Be sure you checkout our guide on how to select a BMS if you’re going to use a lithium-based chemistry.

15 thoughts on “DIY Off Grid Battery Pack From EV Battery

  1. This is honestly really cool. It’s lithium-ion, so I might want to weatherproof it and keep it somewhere outside.. or at least in the garage.

    -T somebody who has had a battery fire

    1. Indeed. Gotta think about the possibility of anyone else having access to it plugging a cord that’s energized with mains AC into it. An XT60/90 connector or Anderson would have been a far better choice.

      1. Or being tired, distracted etc.

        It’s an accident waiting to happen and I’d really prefer to have a specific type of connector that’s unique in my van, home, workshop etc, one of the larger Andersons maybe, so I couldn’t grab the wrong cable

        1. I mean, I don’t think mixing connectors is smart, but lots of unsafe things are just fine as long as you require people to be in their right minds and prepared for the possible dangers in order to be allowed to go near them. For instance things like Sawstop mechanisms are great for saving fingers, but I wouldn’t insist on having one at home. I would rather use a saw cautiously, so that in the case of a normal accident I don’t find out how well the mechanism works.

          1. Or make it impossible to plug a ac 120v plug in by using a pin in the socket and a hole in the special 60v DC cord no accidental miss use but yes safety systems should not have to be used but if you don’t have it you may find out why it’s a bad idea to trust a user to safely use it

          2. Thanks…

            Considering the BMS can instantly cut power if someone inadvertently plugged 120v into it. I’m not worried. Plus it’ll only ever be me using it

  2. The title is misleading. It should read “DIY incendiary bomb from EV battery”. Wooden case, candles (3D printed parts), insufficient cooling and the already mentioned unsuitable connector. Also this contraption might fall apart after a trip on a bumpy road or self destruct on impact.

    1. Actually, this is a pretty common connector among e-scooters from 32v to 72v. But as I’ll be only person ever using it, and I’ve marked it 60v, AND the BMS can auto disconnect on over current or over voltage to the charge side, it’s not a concern.

      Plus, it’s built a lot stronger then you think. It’s not just going to fall apart .. good grief

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