The LaNi₅ alloy is a typical hydrogen-storage material. On the basis of the empirical electron theory of solids and molecules(EET), the valence electron structures of the LaNi₅ alloy and bond energies of main bonds between upper strata and lower strata for substitution of Co andor Mn for partial Ni in the LaNi₅ alloy are calculated. The results indicate that these bond energies increase when Mn is subslituted for Ni₂, or Co is substituted for Ni₁ or Ni₂. When both Mn and Ni are substituted for Ni, the bond energies increase greatly. as a result of which the lifetime of the LaNi₅ alloy increases.