2018/01/01 by Jason B. Quinn, Thomas Waldmann, Karsten Richter +2 · 1 citation
Chemistry · Engineering · #Advanced Battery Materials and Technologies #Advanced Battery Technologies Research #Advancements in Battery Materials #Biomedical engineering #Chemistry #Composite material #Electrode #Energy density #Engineering physics #Ion #Materials science #Specific energy
paper · pdf · doi:10.1149/2.0281814jes
openalex publication_date 2018/01/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
The standard format for cylindrical Li-ion cells is about to change from 18650-type cells (18mm diameter, 65mm height) to 21700-type cells (21mm diameter, 70mm height). We investigated the properties of five 18650 cells, three of the first commercially available 21700, and three types of the similar 20700 cells in detail. In particular, the (i) specific energy/energy density and electrode thickness, (ii) electrode area and cell resistance, (iii) specific energy as a function of discharge C-rate, as well as (iv) heating behavior due to current flow are analyzed. Finally, the production effort for cells and packs are roughly estimated for 21700 cells compared to 18650 cells.