The world runs on rock · Story 3 of 12

The Battery a roll of metal that holds a charge

Your phone, your laptop and more than 17 million new cars a year run on lithium-ion cells. Each one is a tight roll of metal foils and mineral powders, from salt flats in Chile, pits in Australia, mines in Congo and refineries in China.

Scroll to unroll one

Take it apart

Inside the can, a jelly roll

This is a cylindrical cell in the 21700 size, 21 mm across and 70 mm long, the format in many electric cars and power tools. Inside the steel can is the "jelly roll": long ribbons wound tight around a centre pin.

Four ribbons

Cathode aluminium foil coated with a lithium metal oxide, here nickel, manganese and cobalt (NMC)
Separator a porous plastic film: ions pass through, electrons can't
Anode copper foil coated with graphite, a form of pure carbon
Electrolyte a lithium salt (LiPF₆) dissolved in solvent, soaking everything

Flat or round

A phone battery is the same sandwich stacked flat in a foil pouch. Electric cars use hundreds or thousands of cells, round, prismatic or pouch, wired into one pack.

LiNiMnCoCCuAlPFFe

How it works

Lithium, shuttling

On one side, graphite: sheets of carbon rings stacked like pages. On the other, the cathode: layers of nickel, manganese and cobalt bound to oxygen, with lithium tucked between them. A cell stores energy by moving lithium from one side to the other.

Charging

The charger pulls lithium ions out of the cathode, through the electrolyte and the separator, and slots them in between graphite's carbon sheets. Their electrons can't cross the separator, so they go the long way round, through the charger's wire.

Discharging

Use the phone or drive the car, and the ions drift back to the cathode. Their electrons have to go round the outside to meet them, through your screen or motor: that flow is the electricity.

Why these metals

Nickel packs in more energy; manganese and cobalt keep the layers stable as lithium moves in and out. The cheaper lithium iron phosphate (LFP) recipe swaps them for iron and phosphate, and stores less energy for its weight.

Satellite view of turquoise and white lithium evaporation ponds on the brown crust of the Salar de Atacama — Evaporation ponds in the Salar de Atacama, Chile, November 2018. NASA Earth Observatory / Landsat 8 (public domain).

Where batteries begin

Ponds in the driest desert

Under the Salar de Atacama lies brine rich in lithium. It is pumped into shallow ponds and left to evaporate in the sun until the lithium is concentrated enough to refine.¹ Chile mined 19% of the world's lithium in 2025; Australia, digging it from hard rock, 32%.²

Follow the supply

1 · Lithium

Australia 32%, China 21%, Chile 19%, Argentina 7.9% of 2025 mine output.²

2 · Cobalt

DR Congo mined 74% of the world's cobalt, most of it as a by-product of copper around Kolwezi.²

3 · Nickel

Indonesia mined 67% of the world's nickel in 2025, much of it smelted in industrial parks at Morowali and Weda Bay.^2,9

4 · Graphite

China mined 78% of the world's natural graphite.² Many anodes use synthetic graphite instead, made from petroleum coke.

5 · Manganese

South Africa 38% and Gabon 25% of the world's manganese ore.²

6 · Refining

Mining is spread out; refining is not. For copper, lithium, nickel, cobalt, graphite and rare earths, the top three refining countries held 86% of the market on average in 2024, and nearly all recent growth came from China, and Indonesia for nickel.³

7 · Out to the roads

More than 17 million electric cars were sold in 2024, over 11 million of them in China.⁴

8 March 2022

Nickel doubles before breakfast

Less than two weeks after Russia invaded Ukraine, nickel on the London Metal Exchange jumped from a $48,078 close to a record $101,365 a tonne in early trading. The LME suspended trading and cancelled that morning's trades.^5,6

2022 to 2023

Lithium's boom and bust

Battery-grade lithium carbonate in China hit a record of about 590,000 yuan a tonne in November 2022, then fell about 74% by April 2023.⁷

2025

Congo turns off the cobalt

With prices at a nine-year low, DR Congo stopped cobalt exports in February 2025. Prices more than doubled; in October the ban gave way to export quotas.⁸

And the rules

Jan 2020Indonesia bans nickel ore exports to make miners refine at home.⁹
Dec 2023China requires licences for battery-grade graphite exports.¹⁰
Oct 2025DR Congo replaces its cobalt export ban with quotas.⁸

The lines in the model show the size of each reported move, not a full price history.

Six times the minerals

34 kg against 207 kg

The IEA counts about 34 kg of these minerals in a typical petrol car, mostly copper and manganese, and about 207 kg in an electric car with a 75 kWh battery: graphite, copper, nickel, manganese, cobalt and lithium. Steel and aluminium are left out of both. One cube is one kilogram.¹¹

In the electric car

Graphite 66 kg the anode
Copper 53 kg foils, wiring, motor
Nickel 40 kg · Manganese 25 kg · Cobalt 13 kg the cathode
Lithium 9 kg the part that moves

Cheaper every year

$115/kWh

The average lithium-ion pack price in 2024, down 20% in a year, the biggest drop since 2017.¹²

Why "critical"

Every ingredient is on someone's list

Lithium, cobalt, nickel, graphite and manganese are on the critical minerals lists of the US, the EU and others: the cell can't be made without them, and a handful of countries mine or refine most of each.

LiLithiumAustralia 32% CoCobaltDR Congo 74% NiNickelIndonesia 67% CGraphiteChina 78% MnManganeseSouth Africa 38% CuCopperChile 23% AlAluminiumcathode foil PPhosphateLFP cathodes

Next in the series: The Magnet, the rare earths that turn electricity into motion. Before this: The Mind and The Chip.

Sources

Shares of world output are from USGS Mineral Commodity Summaries 2026 via our minerals data; other figures are cited where they appear. The 3D models are illustrations, not engineering drawings; the price lines show reported moves, not price histories. Photo: NASA, public domain.