OK, serious answer. Fechter was giving you the opportunity to calculate the power that would cross your tongue tissues, but the battery current output is also required to do the math.
People care about voltage but it is not the most dangerous factor. The current is the most important cause of damage when the electricity is traveling through body parts.
A taser gun is delivering 50000 volts and very unlikely to cause physical damages. That is because the current that it does supply is limited very low, about 0.002 Ampere.
A 6s RC lipo battery is delivering about 24 v and will cause severe burns, if it is high C-rate especially.
If a 50v battery has a capacity of 1 kw/h and a C-rate of 0.5 C, it will supply 5 Amps (250 watts of power) through your fingers, or tongue. Now, if that battery has 60 C output rate, it will supply 600 Amps (30000 watts of power). The first will be painful and likely cause a small burn, the second will literally explode the tip of your tongue and leave it with 3rd degree burnt tissues.
My 24s RC lipo ebike batteries do vaporize 6ga Anderson connectors if they are shorted. This is about 5 grams of silver plated copper turned into gas and flying debris, throwing sparks 6 ft away. If the shorted connector was attempted to be plugged with bare fingers without the huge Andersons housing, this mistake would cause severe burns even though the electricity never travels through the fingers, only by the radiant heat from the explosion of the connector. So, before trying stupid things with your ebike battery, make sure to know how much current that it is capable of supplying.