Electrics - Battery Storage
Written by Greg Gimlick Electrics Column As seen in the April 2019 issue of Model Aviation.
Learn More About Lipo Battery Basics
Visit www.ModelAviation.com/lipo-battery-basics.
I’m getting away from some of the technical stuff that I discussed in the last two columns, but the feedback to the internal resistance (IR) discussion has been interesting. Further discussion can be found online in the RCGroups "The BattIR Meter Version II" build thread.
Battery Storage
Flying season is upon us and we’re waking up and using our LiPo battery packs, so I want to discuss how to store them safely. Because we’re charging and often storing them that way, they’re more volatile than when they are put away at storage level.
I want you to think about your storage routine. We all have different circumstances, but it’s important to think hard about safety and your home.
I’m not an explosives ordnance expert, nor am I a physicist who can definitively say what is required to contain the forces that are released when a LiPo battery decides to ignite. I do know that much energy is released in a short period, and a lot of smoke and flames are involved. Most of the time the fire is short-lived, but the amount of smoke is enormous. If you saw magnesium burn in your high school chemistry class, that’s what it’s like.
I recently took a long, hard look at how I’ve been storing my battery packs and decided it wasn’t good enough. A concrete bunker would be the best option, but most of us don’t have the space for one. I determined my goals, and here’s how it broke down for me.
- My number one concern is to contain a fire.
- I want something to alarm me to a problem in the garage where batteries are stored.
- I want to have an exit strategy for the stored batteries.
- There should be signs to alert first responders to the presence of LiPo batteries.
- It must also be convenient and help organize my battery packs.
Having laid out my goals, it was off to the internet, friends, and colleagues to sort out the methods employed by others. There was no sense in reinventing the wheel. I opted for the setup that I’m showing here. It might not be exactly right for your needs, but it could be a starting point. The parts count was small.
- A steel truck box with locking handle.
- A concrete backer board.
- Ammunition cans.
- LiPo bags.
- Hazardous materials stickers for the outside door.
- A smoke/fire alarm.
- A wheeled base.
I picked up a steel truck box at my local Tractor Supply Co. store that had a small dent in the top. They discounted it enough to make it reasonable. The box has a rubber seal around the door, but it isn’t so tight that the box is airtight. It’s also big enough to store four ammunition cans side by side, with room on top of them.
Ammunition Can Considerations
I shopped around and found new ammunition cans online at Walmart for $10 each. They come airtight with a solid rubber seal around the top, but because I wanted to vent the can to prevent any explosion, I opted to try two methods.
On the first can, I drilled the dimples on the top to provide a series of 1/8-inch holes to vent smoke and pressure. The problem is that if I did decide to try to move the box while it is venting, the heat/fire would come through the holes around the handle.
On the rest of the boxes, I cut most of the seal out, leaving only enough to supply the pressure to help the lock stay shut. If you remove the entire seal, the top won’t be secure and will open when you pick it up by the handle. I prefer the partial seal because it vents the can downward and away from the handle. This is a personal choice, but don’t use a fully sealed can.
I usually put my packs into a LiPo bag then into the ammunition cans. It’s just another level of containment but probably overkill (if that’s possible) when talking fire safety.
A couple of companies sell wood divider kits so that you can stand the packs on end inside of the cans. If you do this, be sure to watch for wires that could get caught in the top of the can when you close it. That could easily cut the wires and short the pack. I also label each ammunition can with what size battery packs are inside.
Final Setup
My truck box sits on top of a concrete backer board on top of a rolling stand. The idea is that I might be able to roll the whole thing out onto the driveway should something go terribly wrong. It’s also very heavy, so the rolling stand makes it easy to move inside my shop.
The ammunition cans are loaded with batteries and stored in the truck box, and it all sits under an alarm in the shop. I do understand that if one of the packs goes, they all might, but I hope that each box will contain it well enough within the big box to minimize damage.
Wrapping Up
People fight over the best or only way to store LiPo batteries. Do your homework and think about how to increase the safety of your family and home while still enjoying the hobby. Send me photos and descriptions of your method of storage.
Sources:
The BattIR Meter Version II
19 comments
Battery storage
You are correct, good eye!
Battery storage
I wish I could give you a
Batt storage
Batt-Safes are a great
Lipo battery
Storing at "storage level" is
Lipo Safety
This is a great suggestion
Bomb
Comments like this are not
Instead of a box, you might
Good idea Gary, this is one I
battery storage
I do not store my batteries
Battery Storage Ideas
The purpose.....
LiPO Battery Storage
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