In this post I’ve collated the various articles, videos, and papers on energy storage systems I’ve come across. Most is in note form, for my reference. I’ll update it every so often with new findings. If you find any errors, please do get in touch!

Electrochemical

Lithium

Largest

  • Moss Landing Power Plant, 1200MWh 300MW

Cathodes

  • Lithium Nickel Manganese Cobalt Oxide: NMC, LiNixMnyCozO2
    • Features: Good all-rounder
    • Uses: EVs, electronics, power tools, grid storage
  • Lithium Nickel Cobalt Aluminium Oxide: NCA, LiNiCoAlO2
    • Uses: EVs
    • Companies: Panasonic
  • Lithium Manganese Oxide: LMO, LiMn2O4
    • Uses: Electronics
  • Lithium Iron Phosphate: LFP, LiFePO4
    • Uses: Home batteries, EVs
  • Lithium Cobalt Oxide: LCO, LiCoO2
    • Uses: Electronics
  • Lithium Titanium Oxide: LTO
    • Features: Lower energy density
    • Uses: Some EVs, electronics
  • Sulphur

Anodes


Lithium Air

Features

  • Higher energy density (685 Wh/kg at room temperature)
  • Inexpensive to produce
  • Safer (is solid state)
  • Slightly lower energy efficiency

Lithium air chart

Developments


Thin-Film Lithium

Features

  • Better performance, physically flexible

Lithium-ion polymer (LiPo)

About

  • Electrolyte is solid polymer not liquid electrolyte

Uses

  • Electronics

Features

  • Higher specific density, safer

Battery Streak

  • Reduced heat generated from charging → faster charging

https://youtu.be/48vPgAPtkJg


EnergyX

  • Improved technology for extracting lithium
  • Using membranes, solvent extraction, ion sorption

https://youtu.be/xWpLFUUDTiM

https://youtu.be/_NLG9TLRm14


Fast charging developments

  • A team of researchers, led by Professor Noriyoshi Matsumi from Japan Advanced Institute of Science and Technology (JAIST), showcases a new approach to facilitate fast charging using a binder material which promotes Li-ion intercalation of active material.

https://cleantechnica.com/2023/03/05/speeding-up-extreme-fast-charging-capability-in-lithium-ion-batteries/


HOS-PFM

  • The HOS-PFM coating conducts both electrons and ions at the same time. This ensures battery stability and high charge/discharge rates while enhancing battery life from an average of 10 years to about 15 years.

https://cleantechnica.com/2023/03/13/electric-vehicle-batteries-could-get-big-boost-with-new-polymer-coating/


Other Links

https://en.wikipedia.org/wiki/Research_in_lithium-ion_batteries


(Redox) Flow battery

Largest

  • Dalian (China), 400/800MWh 100/200MW

About

  • Two tanks of liquids

Common Types

  • Vanadium
  • Zinc bromine

Features

  • Low density (so big), low charge/discharge rates, (Vanadium particularly) less efficient
  • Long life (30 years+) and little self-discharge
  • Deep discharge (to 0%)
  • Non flammable and recyclable
  • Zinc bromine is very cheap to manufacture and install

Uses

  • Grid, UPS
  • EVs (rapid recharge via replacing electrolyte)

Companies

Vanadium

  • Dalian (China)
  • US Vanadium (USA)

Zinc bromine

  • Redflow
  • Gelion

Links

https://en.wikipedia.org/wiki/Flow_battery

https://en.wikipedia.org/wiki/Zinc%E2%80%93bromine_battery

https://en.wikipedia.org/wiki/Vanadium_redox_battery

https://youtu.be/pQlG46F87Fs

https://youtu.be/2wsSRq-bEm0


Sodium

Sodium-ion (SIB/NIB)

Features

  • Less energy dense than Li-ion
  • Cheap to produce, readily-available materials

Uses

  • Potentially electronics/EVs
  • Stationary storage (until more dense)

Commercialisation

  • Possibly mass produced in 2023

Companies

  • CATL

Links

https://en.wikipedia.org/wiki/Sodium-ion_battery

https://www.tycorun.com/blogs/news/top10-sodium-ion-battery-companies-in-the-world-in-2022


Sodium Sulphur

Features

  • High energy density
  • Safety concerns

Uses

  • Grid

Links

https://en.wikipedia.org/wiki/Sodium–sulfur_battery

https://youtu.be/tHRoefpqMaM


Sodium Aluminium

  • The new sodium-based molten salt battery uses two distinct reactions. The team previously reported a neutral molten salt reaction. The new discovery shows that this neutral molten salt can undergo a further reaction into an acidic molten salt. Crucially, this second acidic reaction mechanism increases the battery’s capacity. Specifically, after 345 charge/discharge cycles at high current, this acidic reaction mechanism retained 82.8 percent of peak charge capacity.

https://cleantechnica.com/2023/02/07/new-sodium-aluminum-battery-aims-to-integrate-renewables-for-grid-resiliency/


Seawater separator

  • Increase lifetime, capacity, efficiency.

https://www.bristol.ac.uk/news/2022/october/seaweed-based-battery-.html


Aluminium

Aluminium-ion

Features

  • Theoretically better energy density than Li-ion
  • Cheap, faster charging
  • Short shelf life

Uses

  • Consumer electronics/EVs

Commercialisation

  • Pilot phase, possibly available in 2024

Links

https://en.wikipedia.org/wiki/Aluminium-ion_battery

https://youtu.be/5B6icvUBNzE

https://youtu.be/n1TBAWlbXKI


Silver zinc

Features

  • High specific energy
  • Can be flexible

Uses

  • Electronics (including flexible ones)

Links

https://en.wikipedia.org/wiki/Silver_zinc_battery


Oxygen

Carbon-oxygen

About

  • Splits CO2 into C and O then re-joins

Features

  • Long term (100+ hr)
  • 3x more dense than Li-ion

Use

  • Grid

Companies

  • Noon Energy

Links

https://www.canarymedia.com/articles/long-duration-energy-storage/noon-energy-raises-28m-for-a-whole-new-kind-of-long-duration-storage

https://cleantechnica.com/2023/01/19/noon-energy-raises-28-million-to-develop-carbon-based-long-term-energy-storage/


Oxygen-ion

About

  • Made from ceramics

Features

  • No degradation over time
  • No rare elements
  • Approx 1/3 energy density of Li-ion
  • Works at 200-400°C
  • Non-flammable

Use

  • Grid

Links

https://www.eurekalert.org/news-releases/983590

https://spectrum.ieee.org/solid-state-battery-no-anode


Chitosan-zinc

About

  • Crustaceans such as crabs, shrimps and lobsters have exoskeletons made of cells that contain chitin, a kind of polysaccharide that makes their shells hard and resistant. This valuable material is abundant in nature and can also be found in fungi and insects, but is usually thrown away as food waste from restaurants and a byproduct of the food industry.
  • Chitin can be synthesised into a firm gel membrane and used as an electrolyte for a battery. By combining this chitosan electrolyte with zinc, Hu’s team was able to create a renewable battery.
  • The battery is 99.7% energy efficient even after 1,000 battery cycles, which is about 400 hours.
  • The batteries are not flammable and the two-thirds of the battery made of chitosan can break down in soil thanks to microbial degradation in just five months, leaving behind recyclable zinc.

Links

https://www.theguardian.com/science/2022/sep/01/crab-lobster-shells-could-used-make-renewable-batteries


Air

Iron Air

About

  • Rusting and unrusting

Features

  • Long term (100+ hr)
  • Cheap (readily available materials), non flammable
  • Low density, slow charging

Uses

  • Grid

Companies

  • Form Energy (USA)

Links

https://cleantechnica.com/2022/12/24/form-energy-picks-weirton-west-virginia-for-iron-air-battery-factory/

https://www.popularmechanics.com/science/energy/a42532492/iron-air-battery-energy-storage/

https://youtu.be/Ui6wWzxCrQ8


Zinc air

Features

  • Long term (100+ hr)
  • Relatively cheap (but more than iron air)
  • Low density, slow charging
  • Issues with dendrite build-up on electrode
  • ~65% efficient
  • Non flammable

Uses

  • Grid

Companies

  • Zinc8 (Canada)

Links

https://youtu.be/Ui6wWzxCrQ8

https://www.rechargenews.com/transition/new-zinc-air-battery-is-cheaper-safer-and-far-longer-lasting-than-lithium-ion/2-1-812068


Solid state

About

  • A technology not a chemistry
  • Mostly seems to apply to lithium-based batteries for now (in part because they are the most popular)

Features

  • More energy dense
  • Safer
  • Potentially longer life
  • Theoretically lower cost

Developments

Reducing short-circuiting

Lithium metal batteries with solid electrolytes have been slow to develop due to mysterious short-circuiting and failure. According to the team, the issue was down to mechanical stress, which was induced while recharging the batteries. Chueh’s team is looking at ways to use these very same mechanical forces intentionally to toughen the material during manufacturing, much like a blacksmith anneals a blade during production.

https://youtu.be/CAfGozXBou0

https://wonderfulengineering.com/these-scientists-have-just-solved-the-mystery-to-evolve-next-gen-lithium-batteries/

https://cleantechnica.com/2023/01/21/bmws-excellent-solid-state-ev-battery-adventure/

Argyrodite

  • Argyrodite as solid-state electrolyte.
  • High Li-ion concentration, high stability.
  • The main obstacle for argyrodite solid-state batteries is to maximize the structure, in order to meet or beat the ionic conductivity of liquid electrolytes. The new research describes the successful synthesis of a high-performing solid electrolyte in a “one-pot” process, that can be carried out at room temperature, under normal pressure, and completed in less than 15 hours.

https://cleantechnica.com/2023/04/03/arg-new-one-pot-solid-state-batteries-deploy-argyrodite-to-solve-high-heat-conundrum/

Isostatic Pressing

  • This process uses fluids and gases like water, oil or argon inside a machine to apply consistent pressure across a battery component, creating a highly uniform material.
  • Could make battery production easier and faster while creating better conditions for energy flow.
  • May also allow manufacturing the three battery layers as a single, dense system rather than creating them separately before joining them.

https://cleantechnica.com/2023/03/28/research-team-supports-isostatic-pressing-for-solid-state-battery-manufacturing/

3D-printed solid state

  • 3D printing instead of roll to roll
  • 40% less material (so cheaper and lighter), smaller machinery, can print in any shape, 80% capacity in 15mins (C5), expects 800/1000Wh/l, longer life than traditional Li-ion

https://www.fastcompany.com/90851150/this-startup-can-3d-print-a-battery-into-any-shape-you-want

https://cleantechnica.com/2023/02/16/sakuu-announces-3d-printed-solid-state-battery-success/


Mechanical

Compressed air (CAES)

Largest

  • McIntosh CAES Plant, 2.9GWh

Features

  • Issues with change in heat as pressure changes
  • 20~70% efficiency depending on method and heating/cooling

Uses

  • Grid
  • Pneumatics

Links

https://en.wikipedia.org/wiki/Compressed-air_energy_storage


Liquid air (LAES)

About

  • Supercool air (more dense) and store

Features

  • ~25% efficient, but 70%+ if heating/cooling captured
  • Modular, bigger = cheaper
  • Long duration

Uses

  • Grid

Companies

  • Highview Power

Links

https://youtu.be/yb1Nuk3_t_4


Compressed CO2

About

  • Compress CO2 into a dome

Features

  • 6~11x more dense than CAES (but still much less than Li-ion)
  • 70-80% efficient
  • Cheaper than Li-ion, LAES
  • 24+ hours duration
  • 30+ year lifespan

Uses

  • Grid

Companies

  • Energy Dome

Links

https://youtu.be/GSzh8D8Of0k

https://youtu.be/LXSSH6ZuOWk


Ocean tanks

About

  • Compresses water/air into underwater tank

Uses

  • Good for offshore wind (tank could be used to anchor wind turbines)
  • Easily scaled
  • 20+ year lifespan
  • 70~80% efficiency possible

Companies

  • Ocean Grazer
  • StEnSea project
  • FLASC project

Links

https://youtu.be/gd1fTJ-csio


Pumped hydro

Largest

  • Fengning Pumped Storage Power Station, 40GWh, 3.6GW

About

  • Pumps water high using energy, releases through generator via gravity to generate energy

Features

  • Low density
  • Requires geographical features - the larger the height difference between the top and bottom the better
  • Can be huge

Links

https://youtu.be/qBW3KpXp1FM


Thermal

Heat used to boil water to power steam turbine, or just moved around for heating directly.

Links

https://www.canarymedia.com/articles/energy-storage/5-reasons-why-thermal-storage-may-finally-be-set-to-take-off


Molten salt

Largest

  • Ouarzazate Solar Power Station, Morocco, 3GWh, 510MW, world’s largest solar thermal

About

  • Salt heated and melted by concentrated solar

Links

https://youtu.be/QbzqLBL-m8I


Molten metal

About

  • Magnesium or Antimony

Features

  • High self discharge rate
  • High energy density
  • Highly scalable
  • Long lifecycle (20+ years), can deep discharge
  • ~80% efficient
  • Cheaper
  • Fairly simple
  • Need to be kept hot so some safety concerns

Uses

  • Grid

Companies

  • Ambri

Links

https://youtu.be/m8751tkBU_Q


Bricks

About

  • Heats bricks to 1500C

Features

  • 40 year lifespan
  • Stay warm for hours or days
  • Simple

Links

https://youtu.be/B3JlTVt0jLw

https://youtu.be/QbzqLBL-m8I


Hot water

Largest

Mustikkamaa heat storage, 11.6GWh, hot water


Sand

Features

  • Seasonal storage
  • 50 year lifespan
  • 3x more energy dense than water
  • Low efficiency if converting back to electricity
  • 8MWh largest right now

Companies

  • Polar Night Energy

Links

https://youtu.be/G6ZrM-IZlTE


Other

Hydrogen

Hydrogen efficiency


Massless

  • The batteries in today’s electric cars constitute a large part of the vehicles’ weight, without fulfilling any load-bearing function. A structural battery, on the other hand, is one that works as both a power source and as part of the structure – for example, in a car body. This is termed ‘massless’ energy storage, because in essence the battery’s weight vanishes when it becomes part of the load-bearing structure.
  • It contains carbon fibre that serves simultaneously as an electrode, conductor, and load-bearing material.
  • The battery has an energy density of 24 Wh/kg, meaning approximately 20 percent capacity compared to comparable lithium-ion batteries currently available. But since the weight of the vehicles can be greatly reduced, less energy will be required to drive an electric car, for example, and lower energy density also results in increased safety. And with a stiffness of 25 GPa, the structural battery can really compete with many other commonly used const

https://www.sciencedaily.com/releases/2021/03/210322091632.htm


Non-rechargeable

Aluminium-air

  • Very high energy density
  • Non-rechargeable without replacing anodes

https://en.wikipedia.org/wiki/Aluminium–air_battery


https://en.wikipedia.org/wiki/Energy_storage

https://en.wikipedia.org/wiki/Rechargeable_battery

https://en.wikipedia.org/wiki/Comparison_of_commercial_battery_types

https://en.wikipedia.org/wiki/Metal–air_electrochemical_cell

https://en.wikipedia.org/wiki/List_of_energy_storage_power_plants

https://en.wikipedia.org/wiki/List_of_largest_power_stations#Storage_power_stations

https://en.wikipedia.org/wiki/Battery_storage_power_station

https://en.wikipedia.org/wiki/List_of_electric-vehicle-battery_manufacturers

https://www.eia.gov/analysis/studies/electricity/batterystorage/

https://www.youtube.com/playlist?list=PLnTSM-ORSgi51JjqvxlP0JTYSU0-910Ks [Battery technology playlist by Undecided with Matt Ferrell]

https://www.ctvc.co/ldes-long-duration-energy-storage-tech/

LDES Sector Compass