Solid-state lithium batteries are a type of rechargeable battery that use a solid electrolyte instead of a liquid one. They offer several advantages over traditional lithium-ion batteries, such as greater energy density, greater safety and better thermal stability.
Solid state lithium batteries are affected by the growth of branch-like metallic filaments. A recent study investigates the formation of these filaments and offers a solution to prevent them from forming while conserving battery power.
Researchers at the Massachusetts Institute of Technology have made a discovery that could pave the way for the development of a revolutionary rechargeable lithium battery. This new design is expected to be lighter, more compact and safer than existing models.
The key to this potential leap forward in battery technology is replacing the liquid electrolyte that sits between the positive and negative electrodes with a much thinner, lighter layer of solid ceramic material, and replacing one of the electrodes with solid lithium metal. This would greatly reduce the overall size and weight of the battery and remove the safety risk associated with liquid electrolytes, which are flammable. But that search was beset by a big problem: dendrites.
Dendrites, whose name comes from the Latin for branches, are projections of metal that can build up on the surface of lithium and penetrate the solid electrolyte, eventually passing from one electrode to the other and shorting out the battery cell. Researchers haven’t been able to agree on what gives rise to these metal filaments, nor has there been much progress on how to avoid them and thus make lightweight solid-state batteries a practical option.
The new research, recently published in the journal Joule in an article by MIT professor Yet-Ming Chiang, graduate student Cole Fincher and five others from MIT and Brown University, appears to resolve the question of what causes the formation of dendrites. It also shows how dendrites can be prevented from passing through the electrolyte.
Chiang says that in the group’s previous work, they made a “surprising and unexpected” discovery, which was that the hard, solid electrolyte material used for a solid-state battery can be penetrated by lithium, which is a very soft metal, during the process. of charging and discharging the battery as the Li-ion moves between the two sides.
This coming and going of ions causes the volume of the electrodes to change. This inevitably causes stresses on the solid electrolyte, which must remain in full contact with the two electrodes between which it is inserted. “To deposit this metal, there has to be volume expansion because you’re adding new mass,” says Chiang. “So, there is an increase in volume on the side of the cell where the lithium is being deposited. And even if there are microscopic flaws, this will generate pressure on those flaws that can cause cracking.”
These stresses, the team has now shown, cause the cracks that allow dendrites to form. The solution to the problem turns out to be more stress, applied in the right direction and with the right amount of force.
Although some researchers previously thought that dendrites were formed by a purely electrochemical rather than a mechanical process, the team’s experiments demonstrate that it is the mechanical stresses that cause the problem.
The process of dendrite formation normally takes place deep within the opaque battery cell materials and cannot be observed directly, so Fincher devised a way to make thin cells using a transparent electrolyte, allowing the entire process to be seen and recorded directly. “You can see what happens when you put compression on the system and you can see whether or not the dendrites behave in a way that is compatible with a corrosion or fracture process,” he says.
The team demonstrated that they could directly manipulate dendrite growth simply by applying and releasing pressure, causing the dendrites to zigzag in perfect alignment with the direction of the force.
The application of mechanical stresses to the solid electrolyte does not eliminate the formation of dendrites, but controls the direction of their growth. This means that they can be directed to remain parallel to the two electrodes and prevented from crossing to the other side, thus rendering them harmless.
In their tests, the researchers used the pressure induced by bending the material, which was formed into a beam with a weight at one end. But they say that, in practice, there can be many different ways to produce the necessary stress. For example, the electrolyte can be made with two layers of material that have different amounts of thermal expansion, so that there is inherent bending of the material, as is done in some thermostats.
Another approach would be to “dope” the material with atoms that would become embedded in it, distorting it and leaving it in a state of permanent stress. This is the same method used to produce the super-hard glass used in smartphone and tablet screens, explains Chiang. And the amount of pressure required isn’t extreme: experiments have shown that pressures of 150 to 200 megapascals were enough to stop the dendrites from passing through the electrolyte.
The required pressure is “compatible with stresses that are commonly induced in commercial film-growing processes and many other manufacturing processes,” so it shouldn’t be difficult to implement in practice, adds Fincher.
In fact, a different type of stress, called stack pressure, is often applied to battery cells, essentially squashing the material in a direction perpendicular to the battery plates – something like compressing a sandwich by placing a weight on top of it. It was thought that this might help keep the layers from separating. But experiments have now shown that pressure in this direction actually exacerbates dendrite formation. “We’ve shown that this type of stack pressure actually accelerates dendrite-induced failure,” says Fincher.
Instead, what is needed is pressure along the plane of the plates, as if the sandwich is being squeezed from the sides. “What we show in this work is that when you apply a compressive force, you can force the dendrites to travel in the direction of compression,” Fincher says, and if that direction goes along the plane of the plates, the dendrites “will never reach the end of the path.” other side.”
This could finally make it practical to produce batteries using solid electrolyte and lithium metal electrodes. Not only would they pack more energy into a given volume and weight, but they would also eliminate the need for liquid electrolytes, which are flammable materials.
Having demonstrated the basic principles involved, the team’s next step will be to try to apply them to creating a working prototype battery, says Chiang, and then figure out exactly what manufacturing processes would be needed to produce such batteries in quantity. Although they have applied for a patent, the researchers do not intend to commercialize the system on their own, he says, as there are already companies working on the development of solid-state batteries. “I would say this is an understanding of failure modes in solid state batteries that we believe the industry needs to know about and try to use to design better products,” he says.
Reference: “Controlling Dendrite Spread in Solid State Batteries with Engineered Stress” by Cole D. Fincher, Christos E. Athanasiou, Colin Gilgenbach, Michael Wang, Brian W. Sheldon, W. Craig Carter, and Yet-Ming Chiang, 18 November 2022, Joule.DOI: 10.1016/j.joule.2022.10.011
The study was funded by the US National Science Foundation, the US Department of Defense, the US Defense Advanced Research Projects Agency and the US Department of Energy.
Contents
Are solid state batteries safer than lithium-ion batteries?
Summary. Solid-state batteries are often considered safer than conventional lithium-ion batteries. In this work, we present the first thermodynamic models to quantitatively evaluate the heat release of solid-state and lithium-ion batteries under different failure scenarios.
Is solid state better than Li-ion? Solid state batteries have a higher energy density per unit area due to their compact size. The energy density of a solid-state battery can be up to ten times that of a lithium-ion battery of the same size.
Are solid state batteries safer? One possible path to battery safety is a solid-state battery that replaces the volatile, flammable liquid electrolyte with a non-flammable solid electrolyte. The safety benefits of this solid electrolyte replacement are widely accepted.
Are solid-state batteries safer than lithium-ion battery?
Solid-state batteries still have the potential to be safer and more energy-dense than conventional lithium-ion cells, said Alex Bates, a Sandia postdoctoral researcher who led the study, in an interview with ScienceDaily.
What are the disadvantages of solid state batteries? Their usable capacity decreases over time, they give off a lot of heat, which means they can require cooling systems that add even more weight, and because they contain liquid electrolyte, they are not stable and can catch fire or explode.
What is the safest type of battery?
In fact, the safest technology is carbon-coated lithium iron phosphate. The capacity may not be as good as their nickel- or cobalt-based equivalents (about 10% less), but they are safe in that they don’t explode or burn when they go crazy (thermal runaway).
Which type of battery is best? Lithium batteries are one of the most commonly used battery types. They offer the highest energy density of any other battery cell, which means they store more energy than other batteries, such as alkaline.
Which battery is safer Li-Ion or Li-Polymer? The lifecycle of lithium polymer is shorter and the batteries store less energy than lithium-ion batteries of the same size. However, Li-poly batteries are safer and also feature fast charging and a low level of self-discharge, which means the batteries won’t discharge too much if you don’t use them for a while.
Why are we running out of lithium?
But rising demand for electric vehicles is straining global lithium supplies. Global purchases of EVs jumped to 6.6 million in 2021 from 3 million the previous year, meaning EVs accounted for 9% of the market, according to the International Energy Agency (IEA).
Why don’t we mine lithium in the US? Despite dozens of potential lithium mines across the United States and Canada, most projects are in various stages of development and many are years away from production, particularly with environmental lawsuits delaying development due to multiple entry points for litigation at law. US regulatory.
Why is lithium running out? Due to shortages of critical materials and vulnerable supply chains, lithium-ion battery production could lag far behind demand. Coordinated action is needed to sustainably increase supply and keep the transition to renewable energy on track.
What can replace lithium? Calcium ions could be used as a greener, more efficient and less expensive energy storage alternative to lithium ions in batteries due to their abundance and low cost, according to a study.
Will the earth ever run out of lithium?
Lithium is well known for its role in laptop and smartphone batteries, but it is also a key component of electric vehicles, again, for creating a power source. Unfortunately, the planet seems to be running out of this important substance. It is also quite rare around the world.
What will replace lithium? Magnesium. Magnesium can theoretically carry a significant charge of 2 more than lithium or sodium. Because of this, batteries made with the material would have greater energy density, more stability and lower cost than the lithium-ion batteries used today, according to the researchers.
How long will it take for Earth to run out of lithium? The supply crisis will not happen immediately. Although the price of lithium has risen more than tenfold in the last two years, there is enough capacity to meet projected demand until around 2025 – and potentially until 2030 if there are enough recycling operations. After that, chronic shortages are expected.
Is there enough lithium on Earth?
Once it’s over, it’s over. While the world has enough lithium to fuel the electric vehicle revolution, it’s less an issue of quantity and more an issue of affordability. Earth has approximately 88 million tons of lithium, but only a quarter of it is economically viable to mine as reserves.
How many years of lithium are left? Because lithium is not an infinite resource. In fact, according to Kipping, once EVs dominate the car market, there’s about 70 years of lithium left before identified global reserves run out.
What happens if the world runs out of lithium?
Running out of Lithium The inability to produce enough Lithium would result in serious delays in the rollout and implementation of electric transport and renewable energy – as such, it is fair to question whether there is enough of the prized element to meet global needs.
Is there enough lithium in the world for electric cars? While the world has enough lithium to fuel the electric vehicle revolution, it’s less an issue of quantity and more an issue of affordability. Earth has approximately 88 million tons of lithium, but only a quarter of it is economically viable to mine as reserves.
Is LiFePO4 the same as LFP?
Lithium Ferro Phosphate (also known as LFP or LiFePO4) technology, which emerged in 1996, is replacing other battery technologies because of its technical advantages and high level of safety.
Is Li-ion the same as LFP? The energy density of an LFP battery is slightly less than a Li-ion battery. Its energy density falls between 90-165 Wh/kg. Verdict: Li-ion batteries have a higher energy density. That’s why these batteries find applications in lower power consumption requirements.
How do I know if my battery is LFP? Some vehicles are equipped with a lithium iron phosphate (LFP) battery. To determine if your vehicle is equipped with an LFP battery, navigate to Controls > Software > Additional Vehicle Information. If your vehicle is equipped with an LFP battery, “High Voltage Battery Type: Lithium Iron Phosphate” is listed.
Are Lithium and LiFePO4 the same? Is LiFePO4 the same as Li-Ion? No way! The LiFePO4 battery has a cycle life of more than 4x that of lithium-ion polymer batteries.
What is the downside of LFP battery?
Related to their lower energy density, LFP batteries often need to be larger – and heavier – than their NCA or NMC cousins. This can reduce an EV’s efficiency and possibly cause more tire wear.
Should you charge the LFP battery to 100% daily? If your vehicle is equipped with an LFP battery, Tesla recommends that you keep your charge limit set to 100%, even for daily use, and that you also fully charge to 100% at least once a week.
Are LFP batteries better than lithium-ion?
They are less susceptible to problems caused by depth of discharge, designed to discharge up to 80-90% of full capacity without long-term damage, resulting in greater range. LFPs also have an advantage over other Li-ion batteries, both in terms of cycle life and safety.
Is the LFP battery the future? Let’s dive into the features to understand why it’s called the future of energy storage. Better cycle life – LFP batteries last longer than other Li-Ion batteries, with approximately 1,000 to 10,000 cycles. Due to this extended lifecycle, it can be used for many applications.
Is the LFP battery better?
In 2020, the Journal of the Electrochemical Society published a report showing that LFP batteries outperform their NMC rivals in various real-world conditions. Authors Yuliya Preger et al. showed that LFPs provide nearly five times more charge cycles than NMCs and provide higher round-trip efficiency.
How many miles does the LFP battery last? The main differences to consider are that the LFP battery has a slightly shorter range, 253 miles, as opposed to the NCA battery, 263 miles.
How long will LFP batteries last?
LiFePO4 batteries, also LFP batteries, are designed to last a maximum of 10 years. They can last for about 5,000 cycles at 80% depth of discharge, which is much longer than lead-acid batteries. Thanks to the long life span of LFP batteries, many people will choose to use them in many applications.
Will the long-range Model 3 have LFP battery? Model Y, Model S and Model X do not have LFP batteries. The RWD Model 3 I have has LFP batteries. The 2022 version has 272 miles on the tires I have.
How do you stop lithium batteries from exploding?
Minimizing the risk of fire in lithium-ion batteries
- Avoid storing at high temperatures. Batteries, or any equipment that uses them, must be kept away from high temperatures. …
- Avoid keeping all items containing lithium-ion batteries together. …
- Avoid overload. …
- Keep the EV under shade. …
- Store dry. …
- Let cool.
Which fire extinguisher to use for lithium batteries? Li-Ion batteries are considered a Class B fire, so a standard ABC or dry chemical fire extinguisher should be used. Class B is the classification given to flammable liquids. Lithium-ion batteries contain liquid electrolytes that provide a conductive path, so batteries are given a Class B fire rating.
Do lithium batteries randomly explode? Fortunately, large explosions caused by lithium-ion batteries are an uncommon occurrence. If they are exposed to the wrong conditions, however, there is a small chance that they will catch fire or explode.
How likely will lithium batteries explode?
According to the technology reporting website CNET, your chances of a lithium battery catching fire are about 1 in 10 million.
Are lithium batteries a fire hazard? Li-Ion Battery Fires The biggest hazard with Li-Ion batteries is the flammable electrolyte stored inside the battery cell. Fires in lithium-ion batteries usually occur when the battery is being charged or when the flammable electrolyte leaks and comes into contact with an ignition source.
How common are lithium battery fires?
If they are damaged or defective in any way, they can cause devastating fires. The US Consumer Product Safety Commission reported that there were more than 25,000 problems involving fires or overheating caused by lithium-ion batteries in a five-year period.
Is it safe to have lithium batteries at home? It is crucial that Li-Ion batteries are stored in a cool, dry environment to maintain battery performance – as well as your safety. Therefore, we recommend storing batteries indoors, away from direct sunlight, excessive heat, ignition sources and flammable substances.
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