What is inside a phone battery, where did it come from, and where does it go?

In numbers

• 1991lithium-ion batteries went on sale
• 2019Nobel Prize in Chemistry

In five stops

1. 1

   Where were its atoms born?

   Lithium is one of the elements that formed, along with hydrogen and helium, in the first minutes after the Big Bang; some of today's lithium comes from then, and some was made by cosmic rays and certain stellar explosions. The battery's cobalt and copper were born in massive stars and stellar explosions, and the carbon in its graphite in stars.

2. 2

   How did nature prepare it?

   Lithium dissolves easily in water, so today it is mostly obtained from brines beneath the salt flats of Chile, Argentina and Bolivia, or from minerals such as spodumene. Cobalt is usually a by-product of copper and nickel mining; most of the world's cobalt comes from the Copperbelt of the Democratic Republic of the Congo and Zambia.

3. 3

   What did people do?

   In the 1970s Stanley Whittingham made the first rechargeable lithium battery; in 1980 John Goodenough developed a stronger electrode from lithium cobalt oxide; in 1985 Akira Yoshino built the first prototype of today's lithium-ion battery. It went on sale in 1991. The three shared the 2019 Nobel Prize in Chemistry.

4. 4

   What happens when we use it?

   When you charge it, electricity from the socket pushes lithium ions in between layers of graphite. When you use the phone, the ions move back to the other side and electrons flow through the circuit to power the phone. The lithium atoms are not used up, they just travel back and forth; but each cycle loses a little, and the battery weakens over the years.

5. 5

   Where does it go next?

   A dead battery should not go in the rubbish: if it is crushed or punctured it can catch fire. Batteries dropped in collection boxes are taken apart at recycling plants, and metals such as cobalt, nickel, copper and lithium can be recovered and used in new products.