Patent ID: 6911279

Claim:
A battery holder for receiving a coin cell with a positive pole and a negative pole whose diameter is smaller than that of the positive pole thereby forming an annular receiving room around the positive pole, comprising: an insulative housing comprising a base plate, a bulge extending upwardly from the base plate, a plurality of chimbs extending upwardly from the base plate and a protrusion at junctions between the base plate and the bulge and between the base plate and at least one of the chimbs, one chimb opposite to the bulge defining an inclined inner surface, the bulge and the chimb together forming a receiving cavity for receiving a coil cell, the insulative housing further defining a passageway through the base plate and a hole through the bulge, the hole further defining a block in an inner wall thereof; and a first and a second contacts each comprising a mating arm and a retention arm substantially perpendicular to the mating arm; wherein the protrusion and the incline inner surface are configured to be received in the receiving room around the positive pole, the retention arms of the first and the second contacts are respectively received in the hole of the bulge and the passageway of the base plate, with the retention arm of the first contact interferentially contacting the block, and the mating arms extend to the receiving cavity and face to each other.