The simple solution to safe charging of LIPO batteries
If you’re into drones, FPV or RC, then you have lithium batteries. In the past several years they have become an integral part of our hobby.
It may be rare, but they do catch on fire. That is why all manufactures caution to charge only while attended. As I got use to charging lithium batteries, I became more and more careless. I like to go to the field with batteries charged, so started charging the night before. Thankfully I was in my shop when I had my first charging fire or my entire house would have burnt down. Others were less lucky, like this New Zealand Homeowner:
After getting the fire out and the smoldering battery out of the house, I had an intense cleanup effort, the battery produced a very heavy black soot that was throughout my entire house, it settled on everything.
I knew I would never charge inside again, unless there was a safe way to do it. I knew charging bags don’t really work, so started thinking about the problem, I felt as a successful aerospace design engineer I could figure out a practical solution.
The Design (Patent Pending)
So after analyzing the problem I designed an insulated double wall steel box that contains the fire and intense heat, the smoke and soot is filtered through a steel and fiberglass flame arrestor which also reduces the heat of the exhaust gases. The clean and relative cool smoke is vented out of the box to prevent the box from exploding. The battery still produces a large quantity of smoke but it is clean and free of soot and will clear out quickly.
So I build a prototype with the help of a trusted manufacturer I worked with for a few years, here's what it looks:
After finalizing the design after successfully testing the prototype with many batteries, I settled for the following dimensions:
The internal box is 9.5x6.5x4 inches. The external dimensions are 12x9x7 inches.
The flame arrester is placed in the box lid by design, as the act of opening and closing the box ensures a clear area around the exhaust holes to further help prevent the chance of a house fire.
With this box you can charge lithium batteries at home unattended in complete safety. To prove my point I set the BAT-SAFE in a cardboard box full of tissue paper to verify that even in this extremely flammable environment the box would perform as designed.
And it worked. In the testing process, I have deliberately overcharged dozens of lipo batteries to the point of exploding. This included batteries of all shapes and sizes, from small to very large. As the design deprives the fire of oxygen, the temperatures inside the BAT-SAFE are reduced further helping to prevent a home fire.
We have also tested an ammo can just to point out why a sealed metal box doesn't provide you with safety.
In addition to preventing fires I also knew the box needed to be light weight, easy to use, and inexpensive. The box will be made from super thin wall steel sheet, will have a magnetic attached charger stand, and a handle for easy transportation. We designed a fire proof lid seal and wire ways allow access for charging wires.
It opens and closes with one hand and will be so convenient to use that it will never be neglected.
We have successfully produced a prototype from some existing box tooling to test out and prove our system, but with your support we will make custom tooling to produce the perfect charging safe box. It will be convenient to use for charging, storage and transporting of Lipo cells in complete safety. And we all can have peace of mind. Please help me produce the BAT-SAFE, and put a stop to the dangers of Lipo charging.
Tooling and Production
I developed and produce a VTOL UAV (Rotormast) with the help of Mike Binder from Roban Limited, a manufacturer located in south China. I teamed up with them on this project again and with their help we found a reliable manufacturer, who is fully integrated into the development process of the final design and stands by to prepare the tooling and go into production.
The tooling of steel sheet molds, stamp and cutting tools in these sizes is however not cheap, please help us turn this project into reality. Please spread the word!
If you have any questions, please feel free to get in touch either through Kickstarter or Facebook. You could also email us at firstname.lastname@example.org and we promise we will get back to you as soon as possible.
What happens after Kickstarter?
BAT-SAFE will be offered at $49 retail plus shipping. We will develop a larger SAFE, too, for those that are in need of.
We will ship the Bat-Safe to anywhere in the world. We have tried our best to make our shipping prices fair and equitable, so that drone and RC owners around Europe will have the opportunity to take advantage of Bat-Safe's safety features. Please note that you may be responsible for duties, fees and taxes applicable to your region.
Proud Supporter of Kicking It Forward: http://kickingitforward.org Creators supporting each other.
Risks and challenges
Most of the risks and challenges are behind us. We have completed a successful sample in 2015, and started designs of the final product with the help of an ISO certified manufacturer overseas. We are experienced in development and manufacturing of consumer products and our manufacturer is an expert in tin box production.
We will re-test the production box with over a dozen battery fire tests to prove it is effective and rate the box with a maximum battery capacity.
We will test out all of our production features to ensure they work as intended. Only after all testing has been completed successfully will we start production.
And we will update you with the test results.
The concept and design is simple significantly reducing the risk of the product not preforming as advertised.
In order to bring the cost down to an affordable amount, we need to order at least 1,000 boxes from the manufacturer. To get there, we are counting on you. Pledge right now and we will put you on the list to be one of the first to receive a BAT-SAFE.Learn about accountability on Kickstarter
- (30 days)