LITHIUM ION BATTERIES WITH HIGH CAPACITY ANODE ACTIVE MATERIAL AND GOOD CYCLING FOR CONSUMER ELECTRONICS
Battery designs are provided that exhibit commercially suitable cycling properties for consumer electronics with silicon based active materials in the electrodes. The batteries can have stacked or wound electrodes and suitable electrode designs.
1 . A lithium ion battery comprising a positive electrode comprising lithium cobalt oxide, a negative electrode comprising a silicon based active material, a separator between the positive electrode and the negative electrode, supplemental lithium and an electrolyte comprising lithium ions, wherein the supplemental lithium is present in an amount to compensate for 110% to 170% of the negative electrode first cycle irreversible capacity loss, wherein the silicon based active material generally has a specific capacity from 800 mAh/g to 2500 mAh/g at a rate of C/3 when cycled from 1.5V to 0.005V against lithium, wherein the lithium ion battery has a balance of negative electrode capacity relative to the sum of positive electrode capacity and supplemental lithium from 1.1 to 1.7 and wherein the lithium ion battery has a 150th cycle discharge capacity at a discharge rate of C/3 discharged from 4.35V to 2.75V that is at least 80% of the 5th cycle discharge capacity at a discharge rate of C/3 discharged from 4.35V to 2.75V, and wherein the negative electrode has an active material loading from 1.5 mg/cm 2 to 8 mg/cm 2 wherein the battery exhibits a volumetric energy density at least 550 Wh/l.
2 . The lithium ion battery of claim 1 wherein the silicon based active material comprises a silicon suboxide-carbon composite.
3 . The lithium ion battery of claim 1 wherein the silicon based active material generally has a specific capacity from 800 mAh/g to 2500 mAh/g at a rate of C/3 when cycled from 1.5V to 0.005V against lithium.
4 . The lithium ion battery of claim 1 wherein the lithium ion battery has a 150th cycle discharge capacity at a discharge rate of C/3 discharged from 4.35V to 2.75V that is at least 85% of the 5th cycle discharge capacity at a discharge rate of C/3 discharged from 4.35V to 2.75V and wherein the negative electrode further comprises carbon nanotubes, carbon nanofibers or a combination thereof as an electrically conductive agent.
5 . The lithium ion battery of claim 1 wherein the lithium ion battery can have a 400th cycle discharge capacity at a discharge rate of C/3 discharged from 4.35V to 2.75V that is at least 70% of the 5th cycle discharge capacity at a discharge rate of C/3 discharged from 4.35V to 2.75V.
6 . The lithium ion battery of claim 1 wherein the positive electrode has a loading from 12 mg/cm 2 to 35 mg/cm 2 and a density of active material from 3.2 g/cc to 4.5 g/cc, and wherein the negative electrode has a loading from 2.5 mg/cm 2 to 7 mg/cm 2 and a density from 0.6 g/cc to 1.2 g/cc.
7 . The lithium ion battery of claim 1 wherein the electrolyte comprises from 6 wt % to 20 wt % fluoroethylene carbonate.
8 . The lithium ion battery of claim 1 wherein the negative electrode further comprises from 12 wt % to 70 wt % graphitic carbon active material relative to the total active material weight and wherein the lithium ion battery has a 300th cycle discharge capacity at a discharge rate of C/3 discharged from 4.35V to 2.75V that is at least 80% of the 5th cycle discharge capacity at a discharge rate of C/3 discharged from 4.35V to 2.75V.
9 . The lithium ion battery of claim 1 wherein the electrodes are wound in a cylindrical shape.
10 . The lithium ion battery of claim 1 wherein the silicon based active material is preloaded with the supplemental lithium prior to assembly of the battery.
11 . A lithium ion battery comprising a positive electrode comprising a lithium metal oxide, a negative electrode, a separator between the positive electrode and the negative electrode, and an electrolyte comprising lithium ions, wherein supplemental lithium is in an amount to compensate for 110% to 170% of the negative electrode first cycle irreversible capacity loss, wherein the negative electrode comprises a physical blend of a silicon based active material, and a distinct graphitic carbon active material with graphitic carbon being 30 wt % to 60 wt % of the active material of the negative electrode, and wherein the lithium ion battery has a 150th cycle discharge capacity at a discharge rate of C/3 discharged from 4.35V to 2.75V that is at least 80% of the 5th cycle discharge capacity at a discharge rate of C/3 discharged from 4.35V to 2.75V.
12 . The lithium ion battery of claim 11 wherein the negative electrode further comprises from 1 wt % to 15 wt % of a conductive additive comprising carbon nanotubes, carbon nanofibers, nanostructured carbon, graphene, carbon black or combinations thereof.
13 . The lithium ion battery of claim 11 wherein the silicon based active material comprises SiO x , 0.1≤x≤1.9 and from 30 wt % to 55 wt % graphitic carbon.
14 . The lithium ion battery of claim 11 wherein the positive electrode has a loading from 10 mg/cm 2 to 40 mg/cm 2 and a density of active material from 2.5 g/cc to 4.6 g/cc, and wherein the negative electrode has a loading from 1.5 mg/cm 2 to 8 mg/cm 2 and a density from 0.5 g/cc to 2.0 g/cc, wherein the negative electrode further comprises an electrically conductive additive comprising carbon nanotubes, carbon nanofibers or a combination thereof, and from 0.5 to 12 weight percent of a polyimide.
15 . The lithium ion battery of claim 11 wherein the electrodes are wound in a cylindrical shape.
16 . The lithium ion battery of claim 11 wherein graphitic carbon is 30 wt % to 35 wt % of the active material of the negative electrode.
17 . The lithium ion battery of claim 11 wherein the negative electrode comprises polyimide.
18 . The lithium ion battery of claim 11 wherein lithium metal oxide comprises lithium cobalt oxide.
19 . The lithium ion battery of claim 11 wherein the lithium ion battery has a balance of negative electrode capacity relative to the sum of positive electrode capacity and supplemental lithium from 0.95 to 1.4.
20 . The lithium ion battery of claim 11 wherein the silicon based active material generally has a specific capacity from 950 mAh/g to 1800 mAh/g at a rate of C/3 when cycled from 1.5V to 0.005V against lithium.
21 . The lithium ion battery of claim 11 wherein the battery exhibits a volumetric energy density at least 600 Wh/l at a rate of C/10 discharged from 4.35V to 2.75V.
22 . The lithium ion battery of claim 11 wherein the electrolyte comprises from 6 wt % to 20 wt % fluoroethylene carbonate.
23 . The lithium ion battery of claim 11 wherein the in the battery has a prismatic shape, a volume from 1000 mm 3 to 50,000 mm 3 and a stack with 7 to 16 layers of positive electrode.
24 . The lithium ion battery of claim 11 wherein the silicon based active material is preloaded with the supplemental lithium prior to assembly of the battery.