That is how I’ve seen them referred to in articles I read.
In a zinc – copper voltaic cell electrons are produced by oxidation of zinc
at the /anode/ which is considered to be the /negative/ electrode since it
"pushes" electrons into the external circuit. The electrons flow through
the external circuit to the /positive/ copper /cathode/ where they reduce
Cu^+2 ions in solution to copper atoms. Ref: Chemical Principles, Masterton
& Slowinski. In this case the anode is negative, cathode is positive.
This is equivalent to the discharge of lithium-based cells since no external
power is applied between the electrodes. In this case the lithium atoms in
the /graphite/ lose an electron and flow through the electrolyte to the
LiFePO4 electrode, and the electrons flow through the external circuit to
the LiFePO4 electrode. Using the above convention, the /graphite/ would be
considered the /negative/ electrode and /anode/.
Here is where the confusion enters:
During *charging* the intercalated lithium atoms in the/ LiFePO4/ cathode
lose an electron and flow through the electrolyte to the graphite and the
electrons flow to the graphite through the external circuit. So by the above
convention ("pushing" electrons) the LiFePO4 electrode would in this case be
the negative electrode, the opposite of when discharging.
Also, in a DC glow discharge the /negative/ electrode is called the
/cathode/. It collects positive ion (cation) current from the plasma and
electron current from the external circuit. The /positive/ electrode is
called the /anode/ and collects electron current from the plasma and
“pushes” electrons into the external circuit. Ref: Gaseous Electronics,
Hirsch & Oskam. Note that external power must be supplied to sustain the
plasma, so this is equivalent to the *charging* half-cycle of a LiFePO4 cell
where the LiFePO4 electrode acts as the anode pushing electrons into the
external circuit.
So it depends on whether there is an external power source applied
(charging, in the case of batteries). I think generally the literature uses
the "discharging" terminology.
Batteries are definitely consumers of energy since they dissipate energy
during both charge and discharge, so you always get less energy out than you
put in.
I thought Dahn said they had just begun studying batteries, but guess I was
wrong.
--
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