Electrodes alone cannot kill a person. The current that can flow through the body delivered through the electrodes kill in at least two different ways. But not all, or even most, electrodes delivered electromagnetic energy to the body. In most cases, such as when an EKG (or ECG) or EEG is taken, the electrodes are used to make a good electrical connection to he body so instruments can measure the electromagnetic energy in the body, generated by nerve and/or muscle cells. The only cases that come to mind where electrodes are used to deliver energy to the body are electrocution, a form of capital punishment used very infrequently these days as states are moving to lethal injection in the thought that it is more humane than electrocution; and electroshock therapy, another practice with waning use. Electrocution kills by heating the body and causing the internal organs to expand and essentially get cooked in place; and a tiny amount of current through the heart is often lethal. Electroshock or electro-convulsive therapy is considered barbaric in most places these days and is only used very infrequently.
I hope that helps. Oh yes, one more thing, do not apply electricity to your body. It's not a good idea. And stay indoors in lightning storms. You don't need electrodes to get electrocuted!
Masters degree in biomedical engineering.