Crunchie Bar Batteries

This hands-on experiment can be used to demonstrate different methods for the separation of battery material prior to recycling, using a crunchie bar, and is relevant to a range of age groups. There are 2 sets of instructions for this experiment – simplified and detailed. These outline identical experiments, but the extent of explanation offered varies depending on the Key Stage of your child. 

You can watch a video of the experiment here, and scroll down for worksheets and more detail.

The aims of the experiment, explanations, and equipment required are all outlined in the worksheets. The suggested Key Stage for each worksheet is outlined below!

(Made by Beatrice Browning & Rosie Madge)

Please send pictures of your experiments to our twitter accounts : @FaradayInst, @Chembameditor and @B_browning. We would love to see how you get on!


Find the simplified worksheet here!

Who are these instructions for?

For guidance, this simplified worksheet is suitable for Key Stage (KS) 1 pupils, who are encouraged to perform simple experiments, ask simple questions, and recognise that they can be answered in different ways.

Focus of simplified experiment

The focus here is less on battery composition/ operation, and more on the different methods can be used for materials separation, with application to a battery.

Throughout the experiment, investigators are encouraged to think about:

  • Appearance of materials after each separation method.
  • How successful the method was
  • Other materials which may be better suited to each separation method.


Find the detailed worksheet here!

Who are these instructions for?

This detailed worksheet is suited to a range of key stages:

  • Lower KS2: as the principal focus is to enable pupils to broaden
    their scientific view of the world around them through exploring ideas about everyday phenomena (lithium ion-batteries are used everyday used in phones and laptops, so this experiment is great to get kids thinking!).
  • Upper KS2: pupils are encouraged to develop a deeper understanding of scientific ideas, through trying out their ideas (This is actively encouraged in the ‘time to think’ sections of the worksheets!).
  • KS3: it is encouraged that students develop scientific understanding to help them to answer scientific questions about the world around them (lithium ion-batteries are used in phones and laptops, and now in electric cars so are becoming even more prevalent in the world around pupils!).

Focus of detailed experiment

The focus here is to learn about the basic components of a lithium-ion battery, and to gain a more comprehensive understanding of battery recycling methods that are currently employed, to encourage discussion on the strengths and weaknesses of these methods. The detailed worksheet also offers other resources for experimenters to go and further develop understanding of battery recycling and research! 

Throughout the experiment, investigators are encouraged to think about:

  • How the method affects the quality of the resultant material.
  • Whether the method is reversible.
  • Other methods which may be suitable for separation.


In the research lab

Lithium-ion battery (LiB) research is a really important part of chemistry, as these batteries are found in everyday portable devices (such as phones and laptops), and even in electric vehicles, such as the Nissan Leaf. LiB research has gained traction in recent years, due to the worldwide movement towards the electrification of the vehicle industry.

In the School of Chemistry, and in various other departments at the University of Birmingham, there are numerous academics, PhD and Postdoctoral researchers who have dedicated their studies to LiB research, though projects led by the Faraday Institution. To find out more about our research at Birmingham please see:

Recycling lithium-ion batteries from electric vehicles

Faraday Institution Research Projects: Lithium Ion

Page Author: Beatrice Browning

Creative Commons License

This work is licensed under a Creative Commons Attribution 4.0 International License.