ELECTRODE, SECONDARY BATTERY, BATTERY PACK, AND VEHICLE

• Main Authors: SASAGAWA TETSUYA, OKI MITSUHIRO, MORIMOTO SAYAKA, YAGI RYOSUKE
• Format: Patent
• Language: English; Japanese
• Published: 03.10.2022
• Subjects: BASIC ELECTRIC ELEMENTS; ELECTRICITY; PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSIONOF CHEMICAL INTO ELECTRICAL ENERGY

To provide an electrode capable of realizing a secondary battery in which a decrease in capacity is suppressed, a secondary battery in which a decrease in capacity is suppressed, and the like.SOLUTION: An electrode 3 having an active material-containing layer 3b containing an active material that undergoes a two-phase coexistence reaction is provided. The active material-containing layer 3b has a main surface including a pair of first sides 21 along first direction 11. A lithium diffusion coefficient DtE in the thickness direction intersecting the main surface of the active material-containing layer 3b in the outer edge portion including a first region 31 in the main surface is higher than a lithium diffusion coefficient DtC in the thickness direction in a center portion 30 of the main surface excluding the outer edge portion. The first region extends along at least one of the pair of first sides and has a first perimeter width FS of 0.03FA or more and 0.25FA or less for a first width FA between the pair of first sides.SELECTED DRAWING: Figure 1 【課題】容量低下が抑制された二次電池を実現できる電極及び容量低下が抑制された二次電池等を提供する。【解決手段】二相共存反応をする活物質を含有する活物質含有層３ｂを具備する電極３が提供される。活物質含有層３ｂは、第１方向１１に沿う一対の第１辺を２１含む主面を有する。上記主面内の第１領域３１を含んだ外縁部における、活物質含有層３ｂの主面と交差する厚さ方向へのリチウム拡散係数ＤｔＥは、上記主面のうち外縁部を除く中心部３０における厚さ方向へのリチウム拡散係数ＤｔＣより高い。上記第１領域は、上記一対の第１辺の少なくとも一方に沿っており、且つ、上記一対の第１辺の間の第１幅ＦＡに対し０．０３ＦＡ以上０．２５ＦＡ以下の第１周縁幅ＦＳを有する。【選択図】図１