Abstract Lately, heat pipes (HP) have found increased application in the cooling systems of radio electronic equipment. The problem of designing HPs with minimum thermal resistance and maximum heat transfer capacity is a real one. One of the ways to solve this problem is by designing new HP powder capillary structures (CS). These possess a number of advantages compared with the known CS. HPs with CSs obtained by the method of cathode electrolyte deposition were studied as an example. The main CS parameters are determined, these being porosity, permeability, capillary rise height and their dependence on the deposition conditions. Experimental HP samples were made; heat transfer performances and their dependence on the deposition conditions are determined. It is shown that the thermal resistance can be reduced to 0.015 K W −1, and the maximum heat transfer rate obtained was of the order of 10 5 W m −2. An example of air-air-type heat exchanger for cooling a power supply cabinet for numerically programmed control devices is made using HPs with cathode-deposited CS. Test results showed that the heat exchanger was reasonable for the given purpose, power dissipation being up to 1.5 kW.