Battery pack and rechargeable vacuum cleaner

Abstract

The invention provides a battery pack comprising an outer case, and a plurality of cylindrical lithium ion secondary batteries accommodated in the outer case in vertical N rows and lateral M rows (N rows≦M rows), with a gap between the secondary batteries, wherein the outer case has a draft port opened in a first wall facing an outer circumferential surface of the secondary batteries in the first vertical row, and an exhaust port opened in a second wall positioned at the opposite side of the first wall, in each secondary battery in the first vertical row and the second vertical row, a part of the outer circumferential surface, which is at a shorter distance from the first wall than any other parts, faces the draft port of the outer case.

1 - 18 . (canceled)  
   
   
       19 . A rechargeable vacuum cleaner comprising a battery pack including an outer case, and a plurality of cylindrical lithium ion secondary batteries accommodated in the outer case in vertical N rows and lateral M rows (N rows≦M rows), with a gap between the secondary batteries, 
 wherein the outer case has a draft port opened in a first wall facing an outer circumferential surface of the secondary batteries in the first vertical row, and an exhaust port opened in a second wall positioned at the opposite side of the first wall,    in each secondary battery in the first vertical row and the second vertical row, a part of the outer circumferential surface, which is at a shorter distance from the first wall than any other parts, faces the draft port of the outer case.    
   
   
       20 . The rechargeable vacuum cleaner of  claim 19 , wherein the battery pack is provided in an intake route or an exhaust route of a motor.  
   
   
       21 . A rechargeable vacuum cleaner comprising a battery pack, 
 the battery pack comprising:    an outer case including first and second walls, the first wall including a draft port portion, the second wall being located opposite to the first wall and including an exhaust port portion;    a first row of cylindrical lithium ion secondary batteries arranged in the outer case to face the first wall, and the first row of cylindrical lithium ion secondary batteries being spaced apart from each other; and    a second row of cylindrical lithium ion secondary batteries arranged adjacent to the first row of cylindrical lithium ion secondary batteries in the outer case,    wherein:    parts of outer circumferential surfaces of the first row of cylindrical lithium ion secondary batteries, each of which is closer than any other part to the first wall, face the draft port portion of the first wall of the outer case; and    parts of outer circumferential surfaces of the second row of cylindrical lithium secondary batteries, each of which is closer than any other part to the first wall, face the draft port portion of the outer case through space defined by the first row of cylindrical lithium ion secondary batteries.    
   
   
       22 . A rechargeable vacuum cleaner according to  claim 21 , wherein the battery pack satisfies the following formulas (1) and (2):  
       0.1 ≦G   1 ≦5   (1)  0.5 G   1 ≦ G   2 ≦ G   1    (2)  
     where G 1  is a gap (mm) between secondary batteries in the first row, and G 2  is a gap (mm) between secondary batteries in the first row and secondary batteries in the second row.  
   
   
       23 . A rechargeable vacuum cleaner according to  claim 22 , wherein the battery pack satisfies the following formula (3):  
       0.2 G   1 ≦ G   3 *≦0.8 G   1    (3)  
     where G 3 * is a gap (mm) between a secondary battery positioned at an end of the secondary batteries in the second row and a secondary battery positioned adjacent to the secondary battery.  
   
   
       24 . A rechargeable vacuum cleaner according to  claim 21 , wherein each secondary battery in the first row has a temperature distribution in which a temperature difference ranges from 2° K. to 10° K.  
   
   
       25 . A rechargeable vacuum cleaner according to  claim 21 , wherein each of the draft port portion and the exhaust port portion comprises a plurality of openings, a total area of the openings of the draft port portion falls within a range of 10% to 80% of an area of the first wall, and a total area of the openings of the exhaust port portion falls within a range of 10% to 80% of an area of the second wall.  
   
   
       26 . A rechargeable vacuum cleaner according to  claim 21 , wherein a heat equalizing plate comprising ventilation ports is interposed between the secondary batteries in the first row and the secondary batteries in the second row.  
   
   
       27 . A rechargeable vacuum cleaner according to  claim 21 , wherein a distance between the first wall and each of the parts of the outer circumferential surfaces of the first row of cylindrical lithium ion secondary batteries falls within a range of 0 to 5 mm.  
   
   
       28 . A rechargeable vacuum cleaner according to  claim 21 , wherein at least part of the outer case is covered with a shock absorbing material.  
   
   
       29 . A rechargeable vacuum cleaner according to  claim 21 , wherein a longitudinal direction of each of the first row of cylindrical lithium ion secondary batteries and the second row of cylindrical lithium ion secondary batteries is parallel to a gravitational direction or orthogonal to the gravitational direction.  
   
   
       30 . A rechargeable vacuum cleaner according to  claim 21 , wherein a ventilation port is formed in at least one of a top and a bottom of the outer case.  
   
   
       31 . A rechargeable vacuum cleaner according to  claim 21 , wherein the outer case further includes a third wall which is perpendicular to the first and second walls and a fourth wall which is located opposite to the third wall, and each of the first to fourth walls of the outer case is formed of at least one kind of metal selected from the group consisting of aluminum, aluminum alloy, magnesium, a magnesium alloy, titanium, a titanium alloy, iron, an iron alloy and a stainless steel.  
   
   
       32 . A rechargeable vacuum cleaner according to  claim 21 , wherein at least one row of cylindrical lithium secondary batteries are arranged adjacent to the second row of cylindrical lithium secondary batteries in the outer case, and the total number of rows of cylindrical lithium secondary batteries in the outer case falls within a range of 3 to 5.  
   
   
       33 . A rechargeable vacuum cleaner according to  claim 21 , wherein the number of cylindrical lithium secondary batteries in the first row and the number of cylindrical lithium secondary batteries in the second row each falls within a range of 2 to 96.  
   
   
       34 . A rechargeable vacuum cleaner comprising: 
 a dust compartment;    an intake member which takes air in the dust compartment to collect dust;    an intake duct provided in between the dust compartment and the intake member;    an exhaust duct for use in exhausting exhaust from the intake member to an outside; and    the battery pack recited in claim  1 , the battery pack being located in the intake duct.    
   
   
       35 . A rechargeable vacuum cleaner comprising: 
 a dust compartment;    an intake member which takes air in the dust compartment to collect dust therein;    an intake duct provided in between the dust compartment and the intake member;    an exhaust duct for use in exhausting exhaust from the intake member to an outside; and    the battery pack recited in claim  1 , the battery pack being located in the exhaust duct.