It’s no secret that lithium-ion batteries are exploding in popularity. With electric cars booming and new battery-based energy storage solutions coming to market, global demands on lithium are increasing substantially. Regulators in certain areas are forcing manufacturers to start recycling batteries from the electric cars they make at the end of their life. Here’s how Tesla may plan to do it.
Components of Tesla Batteries
Tesla batteries are based on a very common and relatively basic lithium-ion chemistry, just altered in such a way that gives them their class-leading battery chemistry.
Tesla’s Model S and X have Panasonic made 18650 cells in their battery packs. The name comes from the cell having an 18mm diameter and a 650mm height. These cells are very similar to the Panasonic NCR18650B cells that have an energy density of 265 Wh/kg.
Each cell consists of Lithium-ion (70%), lead-acid (19.2%), Nickel-based compounds (0.2%), Flow (6.6%), and Sodium based compounds (3.9%). Evidently, the majority of the battery is made of lithium, something that the world has a relatively small amount of.
The ‘lithium triangle’ in South America, consisting of Argentina, Chile, and Bolivia houses 75% of all global lithium supplies. The lithium is extracted on a huge scale from around 130ft below the surface. It is then placed in large, shallow evaporation pools to dry out in the desert sun.
According to current research, there are only 28 million tonnes of lithium in known reserves on the planet. The average electric car uses about 20kg of lithium in one of its battery packs. As a result, we only have enough lithium to sustain about 23 years of an all-electric fleet of electric cars. Hence, we’re clearly in need of a recycling solution.
Lithium-ion Battery Recycling
In the past, lithium-ion batteries have been recycled less so to retrieve the elements in them, but because of the harmful chemicals that they contain. If all Li-ion batteries were thrown to landfill, they could have many harmful consequences to wildlife. Imagine swimming in a sea of battery acid.
The Recycling Process
Hence, li-ion batteries are widely recycled. The process starts with the discharging the batteries to remove any stored energy to prevent fire or thermal problems. The electrolyte is then frozen to prevent electrochemical reactions from taking place whilst the battery is crushed. The batteries are then disassembled into their basic components by a few different processes.
From here on, the process gets quite complicated, so we’ll just focus on the extraction of the lithium itself as that is the main concern here. Most metals can be easily sorted and removed after the battery has been separated but the aluminium and lithium remain. A hydrometallurgical (extracting metals from their ores) process then takes place to remove the lithium from the remaining elements.
This hydrometallurgical process includes leaching, extraction, crystallization, and precipitation from a liquid solution. Leaching is where a solute is extracted from its carrier substance using a solvent and can be a naturally occurring process.
Umicore is a battery recycling facility in Belgium which aims to recover 95% of cobalt, nickel and copper and a large proportion of other elements including lithium.
One of the problems with the process that Umicore use is that it is based upon using a furnace to melt the batteries. This consumes large amounts of energy and has a significant carbon footprint. Fortunately, this would not be so much of an issue if the facility was powered by sustainable energy.
Recycling the batteries and recovering the lithium would dramatically extend the amount of time we have before the global lithium reserves are depleted. However, with the rise of electric cars, the question becomes ‘who is actually going to be recycling all these batteries?’
Certain regulations stand in some areas that force EV manufacturers to recycle batteries from their cars, but these only apply in certain areas. Thankfully, Tesla is ahead of the curve and plans to expand its battery recycling division.
Tesla’s Battery Recycling Plan
As you may know, one of Tesla’s ‘co-founders’ was JB Straubel. Although Musk pushed forward as CEO of the company, Straubel remained the CTO (Chief Technical Officer) at Tesla for a long time. A couple of months ago, he made the decision to step down from this role after 15 years, moving into a senior adviser role in the company.
Although Straubel was branded as the CTO, he was mainly involved in battery research and development. Due to his 15 years of research at Tesla, he is now one of the leading lithium-ion battery experts in the world.
So, Straubel stepped down, but why?
In 2017, he was listed as one of the co-founders of a new company named Redwood Materials. Although their website contains a very limited amount of written information on the company’s aim, we can gather a few things from it.
Firstly, the first (and only) statement on the website reads as follows:
Advancing sustainability through research and development, engineering, and operational excellence for next generation recycling processes and programs.Redwood Materials
Additionally, the logo of the company contains the two ‘O’s joined together like a lemniscate (infinity symbol). The symbol contains arrows and is green, suggesting that Redwood Materials is aiming for some kind of all in one green recycling scheme. The logo is pictured below.
What does this mean?
Let’s just recap quickly. JB Straubel, one of the world’s leading li-ion battery experts stepped down from CTO at the largest electric car manufacturer in the world to start a battery recycling company.
Oh, and to add to that, Redwood materials has recently acquired permits to expand into Nevada, exactly the location of the Gigafactory 1 which makes all of the Telsa batteries.
In the past, Straubel has shared Tesla’s vision of creating a closed-loop recycling system. The idea being that used batteries would come in, elements would be extracted, then they would be used again to create more batteries.
It really does seem like Redwood Materials would be looking to make a partnership with Telsa to recycle their batteries at the Gigafactory to create such a closed-loop system. Although Straubel seems adamant that Redwood Materials has no plans to partner with Telsa, it all seems a bit too convenient.
If Redwood Materials end up developing an efficient, clean recycling process and then partner with Telsa, that would be great news for the whole electric car industry. Perhaps then Redwood Materials would be able to partner with other automakers to recycle their batteries and create closed-loop systems.
Alternatively, it’s completely possible that the two companies will stay separate, with Telsa developing their own closed-loop system and Redwood Materials being contracted by other companies.
One thing is for certain, Musk is no longer the only Tesla executive who has a startup on the side.