Understanding Four Wire Kelvin Probe Testing for Battery Internal Resistance
Four-wire Kelvin testing eliminates lead and contact resistance errors, enabling precise micro-ohm battery internal resistance measurement for cell grading.
Spring Pogo Pins
Meaning
Retractable, spring-loaded electrical contacts establish temporary connections with conductive surfaces during testing and assembly. Utilizing spring pogo pins in automated cell testing ensures consistent contact force despite slight variations in cell height or alignment. This mechanical flexibility is necessary for maintaining stable resistance measurements on fast-moving lines.
Design Features
Each pin consists of a precision-machined plunger, an internal spring, and a barrel. The spring material and preload are selected to deliver a specific contact force at the working travel limit. This construction accommodates physical tolerances in the test fixture.
Electrical Reliability
Reliable current flow requires that the plunger maintains low contact resistance with the cell terminal. Gold or nickel plating protects the tips from oxidation and reduces electrical losses. Proper tip selection, such as serrated or crown shapes, helps penetrate surface contaminants.
Sourcing Management
Procurement teams evaluate the mechanical life of these components, which often exceeds hundreds of thousands of cycles. Sourcing high-durability spring pogo pins lowers the total cost of ownership by reducing the frequency of replacement cycles. Production managers monitor the wear rates of the tips to schedule preventive maintenance before contact issues arise.
Choosing the right supplier ensures a stable supply of replacement parts for the assembly line.