Important items for design with battery holder pole

1)The contact point between the negative electrode and the negative electrode of the battery should be parallel or higher than the central axis of the battery, otherwise the battery is easy to spring out after installation.

2)Compression with battery holder negative electrode: We should make sure the batteries can not be thrown out when battery is loaded, even if there is no battery cover for battery holder. If the negative pole is designed with a spring, the general compression is more than a half, but it depends on the specific size of the spring line diameter, If metal shrapnel is used, the elastic deformation must be calculated.

3) Make a small plane in the middle of the positive battery plate, so that the contact area with the positive battery will be larger than the spherical surface.