The Future of Batteries
It’s not news that climate change is one of the most pressing issues of our time. With 74% of global carbon emissions coming from the road transport sector, coming up with a green alternative to the internal combustion engine is a sensible place to start.
Turning to electric vehicles (EVs) is a solution that makes perfect sense from the perspective of climate change. The challenge lies in the fact that the internal combustion engine is very good at what it does. Until now, lithium-ion batteries have faced a plethora of challenges in replacing fossil-powered internal combustion engines.
Recent advancements in the technology inside these batteries may have the power to change that and help revolutionize an industry that has traditionally been synonymous with smog and fossil fuels. Let’s have a look at how exactly this all works.
Advancing Batteries with Lithium-Ion Technology
In order to understand what makes a lithium-ion battery superior to a nickel or cadmium battery, we need to peel the top layer off and have a look at what’s going on inside. All batteries function on the same concept – an anode (positive) and a cathode (negative) terminal are separated by an electrolyte.
When the anode and cathode are connected to form a complete loop, this causes an electrochemical reaction which causes the flow of electrodes. This results in a charged circuit – the lightbulb is on, and everybody is happy.
As everybody knows well, however, batteries have a tendency to run out of power. That is because the electron flow through the circuit is not the only flow that happens in a battery. The electrolyte also facilitates another electrochemical reaction as ions flow between the anode and the cathode.
When ions flow from the anode to the cathode they discharge the battery and it loses its charge. When they flow in the opposite direction, however, they have the opposite effect and charge the battery back-up.
This is where rechargeable lithium-ion batteries that you can find in your laptop or phone offer a massive improvement over more rudimentary battery technologies which only allowed the ions to flow one way.
While lithium-ion has provided a great deal of advancement towards greener vehicles, it has faced some challenges that have prevented it from becoming the sweeping reform the industry needs.
Challenges to Lithium-Ion Technology
As mentioned, internal combustion engines are very good at their job. They provide an explosion of power which we have learned to harness with centrifugal force to drive our vehicles forward very quickly. As it has been so effective at its task, we have also built our entire infrastructure to support it.
Business and supply chains are based around the results that it delivers and the economics of that have impacts on our whole society. Truly does our relationship with the internal combustion engine run deep.
To provide a truly practical alternative to fuel, batteries must be developed to outperform the explosive power of the internal combustion engine. Let’s examine what our lithium-ion technology has been up against, and where it has traditionally fallen short.
Performance-wise, the power of an explosion is a very difficult contender to beat when it comes to driving acceleration. When people hit the pedal, they expect a certain amount of force to move them from under the hood. Traditional EVs haven’t had the ability to replicate that power, although Tesla has circumnavigated this obstacle by stacking up the number of cells within the battery to give it more power, faster. We’ll elaborate on this below.
The ability to hold a charge for a long period of time has always been the challenge of battery tech. The maximum range of EVs is about 300 miles. With challenges like these, it’s no wonder that lithium-ion hasn’t swept the industry, but that may be about to change.
Enter the Solid-State Lithium (SSL) Battery
One innovation that is promising to make these challenges a thing of the past for EVs, is SSL technology. The difference between a lithium-ion battery and an SSL battery is actually comically simple. In lithium-ion batteries, the semi-permeable electrolyte is a liquid or a gel. In an SSL battery, the electrolyte is solid.
While this may seem like a simple difference, the effect it has on the performance and storage capabilities of the battery, however, is staggering.
Higher energy density gives the SSL battery the jump on lithium-ion’s performance issues in EVs. There are 2 ways to get a higher power density out of a battery. Increase the cells, or slow down the ions.
While Tesla’s approach to this problem worked to increase the charge, their lithium-ion technology is unable to compete with SSL because the gel or liquid electrolytes in the cell are not as stable.
Liquid and gel electrolytes cannot be exposed to air, are volatile and extremely flammable. This is not ideal for the end-user and also causes more challenges for manufacturers.
Solid-state lithium batteries also store more power. The ability to store more power and give 2.5 x the power density of preceding technology affords auto designers many benefits when it comes to weight displacement, acceleration abilities and range.
That makes SSL batteries easier to produce, higher-performing, longer-lasting and safer than lithium-ion technology. That is the kind of innovation that we need to see, and it carries some lessons with it that could be hard-learned if not heeded. The technology that we’ve all grown to depend upon – whether green or not, exists for a reason.
There can be no product without the problem which it addresses. With this, we learn that technology that exists for the sake of greener solutions must also address the problem its predecessor solved competitively – or better.