Multi-Layered Anode Containing Silicon-Based Compound and Lithium Secondary Battery Including the Same

A lithium secondary battery, comprising:

• a cathode, an anode, a separator interposed between the cathode and the anode, and an electrolyte, wherein the anode comprises:
• a first anode active material layer formed on at least one surface of an anode current collector, wherein the first anode active material layer contains a mixture of natural graphite and artificial graphite as the anode active material and a first binder respectively;
• and
• a second anode active material layer formed on the first anode active material layer, wherein the second anode active material layer contains a mixture of artificial graphite and a silicon-based compound as the anode active material and a second binder respectively,
• wherein a high temperature lifetime retention of the lithium secondary battery is more than 66%, wherein the high temperature lifetime retention is measured by charging the secondary battery at 1 C to 4.35V/38 mA under current/constant voltage (CC/CV) conditions at 45° C. and then discharged at 2 C to 2.5 V under constant current (CC) conditions, wherein charging and discharging is repeated 1000 cycles, wherein the high temperature lifetime retention (%) is calculated by the following:
• (
• capacity
• ⁢
• after
• ⁢
• 1000
• ⁢
• cycles
• /
• capacity
• ⁢
• after
• ⁢
• 1
• ⁢
• cycle
• )
• ×
• 100.

A lithium secondary battery, comprising:

• a cathode, an anode, a separator interposed between the cathode and the anode, and an electrolyte, wherein the anode comprises:
• a first anode active material layer formed on at least one surface of an anode current collector, wherein the first anode active material layer contains a mixture of natural graphite and artificial graphite as the anode active material and a first binder respectively;
• and
• a second anode active material layer formed on the first anode active material layer, wherein the second anode active material layer contains a mixture of artificial graphite and a silicon-based compound as the anode active material and a second binder respectively,
• wherein a temperature at which a maximum peak with a largest heat flux appears when measured by differential scanning calorimetry (DSC) while increasing the temperature from room temperature to 500° C. at 10 t/minute is 292° C. or higher.