Lithium-Ion batteries are highly successful high-energy-density commercial energy sources used to run consumer devices such as cellphones, E-bikes, hoverboards, laptops, tablets, and medical equipment. They are safe if produced with attention paid to the selection of materials and to the manufacturing methods used for their production and quality control processes. However, safety hazards arising from rare manufacturing defects have given them notoriety as devices to be handled with utmost care. This manuscript provides an account of the safety-related chemistry of Li-ion batteries and the processes used to manufacture and utilize them safely.