Tesla Researchers Tout 100 Year Battery Design

Researchers at US electric car giant Tesla have touted a new electric vehicle (EV) battery that could last 100 years before it needs replacing.

Tesla founded its Advanced Battery Research division in 2016 in Canada, which is currently led by Dr Jeff Dahn at Dalhousie University in Halifax, Electrek reported.

Dr Dahn is said to be considered as a pioneer of Li-ion battery cells. Indeed, according to Electrek he has been working on the Li-ion batteries pretty much since they were invented, and is credited for helping to increase the life cycle of the cells, which helped their commercialisation.

100 Year Battery

His work at Tesla’s Advanced Battery Research division is now focusing on a potential increase in battery energy density and durability, while also decreasing the cost.

According to Electrek the division has already produced a number of patents and papers on batteries for Tesla. The EV car giant recently extended its contract with the group through 2026 as it added two new leaders to be mentored by Dr Dahn.

Now one of those new leaders, Michael Metzger, along with Dr Dahn and a handful of other boffins, have been named as authors of a new research paper that has been lumbered with the catchy title of “Li[Ni0.5Mn0.3Co0.2]O2 as a Superior Alternative to LiFePO4 for Long-Lived Low Voltage Li-Ion Cells”, which has been published in the Journal of the Electrochemical Society.

In the research paper Dr Dahn and his team describe a nickel-based battery that would be able to overcome the energy density and durability limitations of a lithium iron phosphate (LFP) battery, while offering a vastly improved life cycle that could reach 100 years under optimal conditions.

If this work, it would be a noteworthy battery improvement, and would help remove one of the concerns people may have about switching EVs.

Typical EV concerns are centred around battery range anxiety; the lack (certainly in the UK) of suitable charging infrastructure; and concern that an EV’s battery pack would need to be replaced every eight years (a potentially costly exercise) which could limit the effective lifespan of the EV.

A combustion engined car typically has a longer lifespan than this, with regular maintenance and part replacements.

So the development of a much longer lasting EV battery could be a game-changer in advancing the move to EVs.

Improved longevity

The research paper describes a nickel-based battery chemistry meant to compete with LFP battery cells on longevity while retaining the properties that people like in nickel-based batteries, like higher energy density, which enables longer range with fewer batteries for electric vehicles.

According to the research paper:

Single crystal Li[Ni0.5Mn0.3Co0.2]O2//graphite (NMC532) pouch cells with only sufficient graphite for operation to 3.80 V (rather than ≥4.2 V) were cycled with charging to either 3.65 V or 3.80 V to facilitate comparison with LiFePO4//graphite (LFP) pouch cells on the grounds of similar maximum charging potential and similar negative electrode utilization. The NMC532 cells, when constructed with only sufficient graphite to be charged to 3.80 V, have an energy density that exceeds that of the LFP cells and a cycle-life that greatly exceeds that of the LFP cells at 40 °C, 55 °C and 70 °C. Excellent lifetime at high temperature is demonstrated with electrolytes that contain lithium bis(fluorosulfonyl)imide (LiFSI) salt, well beyond those provided by conventional LiPF6 electrolytes.

The cells apparently showed an impressive capacity retention over a high number of cycles.

The research group even noted that the new cell described in the paper could last a 100 years if the temperature is controlled at 25C.

Musk claims

It should be remembered that battery technology is advancing all the time.

In October last year, Japan’s Panasonic (a supplier of batteries to Tesla) unveiled a more advanced prototype battery, that has five times the storage capacity of existing batteries.

That new prototype could help Elon Musk meet his long-touted goals for EV cars.

In September 2020 Tesla finally held its long awaited battery day event, and while Musk had made a number of claims beforehand, it disappointed with no news of breakthrough battery advances.

Instead Elon Musk at the time announced the Plaid powertrain for the Model S; a ‘tabless’ battery cells design for improved range and performance; a move towards eliminating cobalt in its batteries altogether; a new cathode plant to streamline its battery production; and finally Tesla’s ambition to produce a $25,000 (£19,600) car.

But the September 2020 event fell flat of Musk’s earlier promise to investors that the technology revealed at the battery day “will blow your mind”, and there was no announcement about the so called “million mile” battery.

Musk in August 2020 had suggested Tesla may be able to mass produce longer-life batteries with 50 percent more energy density in three to four years.