Seriously, go to the junk yard and get a very old battery.
1st, short the battery w/ a wire to be sure there is no arc.
2nd, take an ammeter and place the setting on the highest current and short it across the battery, check for indication working down to micro amps. This will give an indication of any current or life in the battery.
3rd, do you have access to a spectrum analyser, or an electromagnic receiver (hi proformance radio), and antennas rod, biconical, and conical log. A simple set up to measure electro-magnetic interference (EMI) radiation can be performed.
Set up the receiver and antennas then short out the battery and check measurements.
As a free note, there are companies that do that sort of measurement for the military. If you are working for the dis. channel ( if its not tax payers money), have a military contractor do the test.
I did work in this field for a while, that where I gained my knowledge.
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