What is the most eye-catching high-tech you have ever seen? Recently, I saw a video of a man surfing at the seaside, and the surfboard he used was somewhat different.
I wonder if anyone has seen the ground nail shoes used by shoemakers before. This surfboard is a little like it. People can slide vertically on it, just like flying with a sword. What is its working principle? Why can a small board "hang" hundreds of kilograms of people on the water?
An electric surfboard that can "hang" on the water
When it comes to surfing, people who like marine projects should like this. In the past, traditional surfing equipment relied on the waves of the sea. However, with the development of technology, electric surfboards have become a new equipment.
The biggest feature of this electric surfboard is that it can surf through its own electric device without waves.
However, its power comes from an internal lithium battery, which can provide about an hour of kinetic energy. In addition to entertainment, this surfboard also has a "rescue mode". Although it has a strange shape and is very cool to use, its price is really beyond the reach of many people. It is reported that the retail price of such a surfboard is 5000 dollars.
Working principle of electric surfboard
The shape of this surfboard is very strange. In addition to the "deck" where people stand, a long pole is connected below, and a small hydrofoil is installed at the bottom of the pole.
This hydrofoil is the core component of the electric surfboard. It looks like the wing of an airplane. Using Bernoulli's principle, the pressure is low where the flow rate is high, so a significant pressure difference can be formed on both sides of the hydrofoil.
Then, driven by the propeller, the surfboard can slide forward. When the speed increases, the pressure difference on both sides of the hydrofoil will also increase, so that the surfboard can be lifted out of the water. It looks like "flying" on the water. The operator only needs to master the balance, and the speed and direction can be controlled through the remote control in his hand.
Why can lithium batteries work in the sea?
As we said earlier, the power source of this electric surfboard is the underwater propeller, and the rotation of the propeller is driven by a built-in lithium battery. Then the question arises: Why can the lithium battery work in the water?
First of all, we should know that lithium batteries are made of lithium metal or lithium alloy as positive and negative electrode materials and use non-aqueous electrolyte solutions. However, due to the very active chemical properties of lithium metal, the processing, storage and use of lithium metal have very high environmental requirements.
However, under normal circumstances, lithium batteries are prone to short circuit when encountering water, especially when the water contains sodium ions. Someone once did an experiment and threw a lithium battery into the water conservancy. As a result, the battery directly exploded.
But why is the lithium battery in the electric surfboard OK? First, it is in a closed environment, and seawater will not enter the lithium battery. In addition, it also has a certain waterproof device. As long as the surfboard is not damaged, the battery will not explode generally.