Yes folks, things are going to be molten (hot) and they are going to work as a battery. Take this example: Magnesium, salt and antimony at above 600 celcius contained in an insulated shipping container size box will work as a battery.
How does liquid metal battery work ?
There are three layers in the liquid metal battery. Like any other battery there are two electrodes and an electrolyte. The top layer is the low density metal which is the negative electrode, then a salt which is the electrolyte and finally the high density metal which will be the positive electrode. Even though they work in molten state they don’t mix because they are insoluble and form layers.
When a device or load is connected and the battery has to discharge, the metal of the top electrode wants to form alloy with the bottom electrode but they are not soluble so the only way to do this is when it forms ion. So it becomes the ion which goes through the electrolyte and meets the positive electrode to form neutral metal. At the same time the electrons generated goes though the external circuit to produce electricity. The bottom layer becomes thicker and the top layer thins. The reverse is true when charging the battery, returning it to the same initial state.
Advantages of liquid metal batteries
- Batteries operating at elevated temperatures can cycle with very high charging and discharging rate and further can be deep discharged thousands of times without any charge fade hence no loss of capacity.
- These batteries also require very little maintenance and the metals used can be recycled again and again.
- There is no requirement of elaborate thermal management like lithium ion batteries.
- Cheap and abundant metals can be used as electrodes so the system is inexpensive.
- The system is insulated and self-heating when in operation although initial heating is required.
- Multiple systems placed together on site are connected in parallel, enabling unlimited upward scalability for large-scale projects.
- Cells are also highly tolerant of over-charging or over-discharging, and are not subject to thermal runaway, electrolyte decomposition etc.
- This is a great solution for large scale capacity requirement to combat intermittent supply from solar and wind.
Disadvantages of liquid metal batteries
- They are fairly large so will only be suitable for systems requiring more power and having enough space to house them.
- Since molten metals are maintained at high temperatures some complications like corroding of containers etc have been seen and studied upon.
- It is still at development phase even though the products are out in the market.
About Ambri and its stock
Ambri haven’t gone public yet so no stocks to buy for now.
Ambri batteries were born in the GroupSadoway lab at Massachusetts Institute of Technology where professor Donald Sadoway worked with David Bradwell to develop the Liquid Metal Battery technology.
Ambri’s commercial systems will be packaged in 500 to1500 VDC containers with up to 1 MWh of capacity. These containers will be factory assembled and shipped to site fully populated and sealed and will require minimal maintenance. Each of these containers will contain no replaceable or serviceable components. This eliminates on-site maintenance and means that the container becomes the modular and replaceable system component.
They are experimenting with newer materials with lower melting points, perfecting sealing the containers etc among other things to improve upon.
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The liquid metal battery research was pioneered by Professor Donald Sadoway at the Massachusetts Institute of Technology using various metals. These batteries may have longer lifetimes than conventional batteries, as their metal electrodes go through a cycle of creation and destruction during the charge and discharge cycle, which makes them immune to the degradation unlike conventional battery electrodes.
Such large-scale storage would also make today’s power grid more resilient and efficient, allowing operators to deliver quick supplies during outages and to meet temporary demand peaks without maintaining extra generating capacity that’s expensive and rarely used.