A Primer to the Use of Alternatives to lithium-ion batteries

This is taken from a more detailed and longer write-up on alternatives to lithium-ion batteries. It has been edited and comments have been added. Sometimes when you write a long piece, people just quit reading halfway through it. My point here is to get people to read what is out there and where we are with alternative power sources beside gasoline driven motors.

We are still a long way away from having a long term and suitable replacement for energy derived from oil powered vehicles and an infrastructure supporting it. It is a good read.

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Six Alternatives to lithium-ion batteries: What’s the future of energy storage? android authority, Calvin Wankhede.

Smartphones to electric vehicles, batteries single-handedly power some of the single most impactful technologies in our lives. While batteries themselves are not some new technology, the lithium-ion (Li-on) battery powering most of our devices only began gaining ground a few short decades ago. 

How do Rechargeable Batteries Work?

Every battery is made up of a cathode (positive electrode), an anode (negative electrode), and an electrolyte medium. When you drain a charged battery, positively-charged ions move from the anode to the cathode. This also triggers a flow of electrons, which can be used to power electronic devices. And when you charge a battery, the same process takes place in reverse.

All in all, you get a cycle that allows charging and discharging of rechargeable batteries. A Li-on battery works the same way and for hundreds of times. 

Lithium Batteries and Why are they Problematic?

• Safety: Lithium is a highly reactive and flammable metal. Li-on (Lithium) battery needs to be kept at a certain temperature and in conditions that do not allow overcharging or short circuits. Failing to do such and these batteries have the tendency to catch fire or even explode due to a chain reaction known as thermal runaway.

AB: My own experience was with an AA batteries. It did not place in the holder properly, loosened up from the positive terminal, and was starting to short. It got hot and I let it fall to the ground.

• Scarcity: Lithium is a key component of Li-on batteries. We only have a limited amount of it on our planet. Moreover, the majority of Lithium reserves are located far from manufacturing centers.

AB: New and large source of high grade lithium was found in an extinct volcanic crater between Oregon and Nevada.

• Sustainability: Li-on batteries require environmentally destructive mining practices for metals such as lithium, cobalt, and nickel. A large amount of these metal resources are in developing countries such as the Democratic Republic of Congo. Ethical mining practices have not been established in these areas yet, meaning Li-on production contributes significantly to greenhouse gas emissions.

• Durability: You may know that smartphone batteries don’t last forever. Most manufacturers only guarantee battery performance for about 800 to 1,000 charge cycles. That’s roughly one charge every day for three years. Li-on batteries tend to degrade over time.

Lithium-ion battery alternatives

Sodium-ion batteries

Not too distant from Lithium-ion batteries functionality are Sodium-ion batteries. Sodium-ion batteries simply replace lithium ions as charge carriers with sodium. This single change has a big impact on battery production as sodium is far more abundant than lithium. In fact, you can use salt from the oceans to extract sodium just about anywhere in the world. This could also lower the cost of battery production as you no longer have to worry about storage and transportation of a potentially dangerous material like lithium.

Sodium ions are physically larger than lithium, which translates to lower energy density. In the real world, this can result in lower range for electric vehicles and shorter runtimes for smartphones. 

Lithium-Sulfur batteries

Lithium-ion batteries use cobalt at the anode, which has proven difficult to source. Lithium-sulfur (Li-S) batteries could remedy this problem by using sulfur as the cathodic material instead. In addition to replacing cobalt, Li-S batteries offer a few advantages, namely higher energy density and lower production costs.

The biggest problem with lithium-sulfur batteries at the moment relates to their fast degradation rate.

Solid-State batteries

Lithium-ion batteries use a liquid electrolyte medium that allows ions to move between electrodes. The electrolyte is typically an organic compound that can catch fire when the battery overheats or overcharges. To reduce this risk, researchers devised an alternative in the form of solid-state batteries. These use a solid inorganic electrolyte, which can sustain harsh environments and wild swings in temperature.

Besides a lower risk of ignition, solid-state batteries can also hold more energy compared to Li-on counterparts. The greater conductivity of a solid electrolyte should also lead to faster charging times. Meaning, we should see better capacity and charging speeds from devices that move to this technology.

Hydrogen Fuel cells

While not exactly similar to a rechargeable Li-on battery, Hydrogen fuel cells emerged as a popular alternative to supply clean energy. It involves combining stored hydrogen gas with oxygen in the air to produce electricity and water vapor. In other words, the byproduct of the reaction is completely environmentally friendly.

The downsides to hydrogen fuel cells? In the automotive industry, you need to build a network of hydrogen filling stations. It’s also quite expensive to build hydrogen fuel cells.

Aqueous Magnesium batteries

Another attempt to make rechargeable batteries less dangerous and harmful has researchers proposing the use of magnesium ions as charge carriers. This has a few advantages, starting with magnesium’s abundant availability and higher ionic charge compared to lithium. The latter means you get higher energy density from the same-sized cell. Finally, these batteries also use an aqueous electrolyte (water) instead of a flammable organic liquid.

The technology is in the early stages of research. It faces several limitations preventing it from serving as a lithium-ion battery alternative anytime soon. For example, existing cathode materials that work with lithium can’t be used for magnesium. And the use of an aqueous electrolyte puts a cap on the battery’s maximum voltage because water breaks down at higher voltages.

Graphene batteries

Graphene is a single layer of carbon atoms, arranged in a hexagonal lattice or honeycomb-like structure. A sheet of graphene is so thin, it’s practically regarded as a two-dimensional structure. This unique property lends itself well for battery production as it also has excellent electrical conductivity, low weight, and a strong physical structure. In 2021, Chinese carmaker GAC announced a breakthrough in graphene battery technology, achieving an 80% charge in just eight minutes.

We’ve seen a lot of buzz surrounding graphene as a lithium-ion battery alternative. However, commercial products remain unviable for now. Cost is perhaps the biggest reason why the industry hasn’t embraced it yet. At over $60,000 per metric ton, graphene is currently used in very small amounts.

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The technology will evolve over time and into one source of energy unless we have more infrastructure to support more sources. If we think of gasoline stations and then electric charging stations, there are quite a few places for each. The latter being more time consuming to get enough energy stored. Just some thoughts.