Back to results
US 2007/0184338 A1Published application
Secondary battery
AssigneeHitachi Vehicle Energy, Ltd.
InventorsTooru Kojima, Takenori Ishizu
Life of this patent
Estimating the term…
Loading patent…
Loading patent…
AssigneeHitachi Vehicle Energy, Ltd.
InventorsTooru Kojima, Takenori Ishizu
Estimating the term…
A secondary battery having an excellent capacity maintenance factor or charging/discharging efficiency is provided. A lithium-ion battery comprises an electrode group that a positive electrode and a negative electrode which respective of active materials for the positive and negative electrodes is coated on both surfaces of a collecting member. An area S1 of a portion of then egative electrode 7 not facing the positive electrode 6 is set to be not more than 10% of an area S2 of a portion of the negative electrode 7 facing the positive electrode 6. An influence that the portion not facing the positive electrode affects a battery reaction is controlled, and the decrease in the capacity maintenance factor or the charging/discharging efficiency according to cycling use can be depressed.
A secondary battery comprising an electrode group that a positive electrode and a negative electrode which respective of active materials for the positive and negative electrodes is coated on both surfaces of a collecting member or is filled into the collecting member are placed via a separator, wherein, with respect to an electrode having a polarity placed at an outside of the electrode group, an area S1 or a capacity C1 of a portion not facing an electrode having an opposite polarity is set to be not more than 10% of an area S2 or a capacity C2 of a portion facing the electrode having the opposite polarity (S1/S2<=10% or C1/C2<=10%).
Dependencies are inferred from the claim text.