So we all know batteries burn... but do we know what exactly does burn? What is inside this tiny metal cylinder that scares so many of us? We try to understand it a bit more with Dr Francesco Restuccia of Kings College London, who is an expert in battery fire safety and self-heating. And this combination of skills gave him a unique view of the challenges of fire safety of batteries - especially the ones that are stored in warehouses and not fueling anything. Francesco takes me on a journey into the world of cathodes, anodes and electrol... I mean battery juice.  Knowing what is inside and why it burns is fundamental to understanding how can we protect the world from the risks arising from Li-ION batter technology. And I hope this podcast episode is a concise introduction to this! And here is a paper choice curated by Francesco, containing the important papers discussed within the episode (because we discuss real science here! :)) X. He, C. Zhao, Z. Hu, F. Restuccia, F. Richter, Q. Wang, G. Rein. The effects of heat transfer on accelerating rate calorimetry of thermal runaway of Lithium-ion batteries, Process Safety and Environmental Protection, VVol 162, 2022, pp 684-693. X.He, Z. Hu, F. Restuccia, H. Yuan, G. Rein. Self-heating ignition of large ensembles of Lithium-ion batteries during storage with different states of charge and cathodes, Applied Thermal Engineering, Vol 197,  2021, 117349. Z. Hu, X. He, F. Restuccia, G. Rein. Anisotropic and homogeneous model of heat transfer for self-heating ignition of large ensembles of Lithium-ion batteries during storage, Applied Thermal Engineering, Vol 197, 2021, 117301. 3P. Christensen, Z. Milojevic, M.S. Wise, M. Ahmeid, P.S. Attidekou, W. Mrozik, N.A. Dickman, F. Restuccia, S.M. Lambert, P.K. Das. Thermal and mechanical abuse of electric vehicle pouch cell modules, Applied Thermal Engineering, Vol 189 2021,116623L. Diaz Bravo, X. He, Z. Hu, F. Restuccia, M. Marinescu, J. Barreras, Y. Patel, G. Offer, G. Rein. Meta-review of fire safety of Lithium-ion batteries: industry challenges and research contributions, Journal of the Electrochemistry Society Vol 167 090559, 2020. X. He, F. Restuccia, Y. Zhang, Z. Hu, X. Huang, J. Fang, G. Rein. Experimental study of self-heating ignition of lithium-ion batteries during storage: effect of the number of cells, Fire Technology, Vol 56, 2020, pp 2649–2669