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I meant for the initial chargeup of the cap

When a discharged cap is connected to a battery it does form a complete circuit, and it will appear as a short circuit to the battery until it charges up. Current of hundreds of amps can flow for a short time during that period. The only thing limiting the charging current will be the impedance of the cap and the battery.

My thought is to connect a small (a few ohms) resistor between the positive of the battery and the cap to slow down the charging process when first constructing the unit and whenever the battery is replaced or the cap is discharged. This will prevent damage to the cap or battery from excess current, and since no current flows from the BGT to the audio gear it shouldn't affect the performance of the BGT in normal use.

Ohms law states that I=V/R, so even a 2ohm resistor will limit current to 9V/2ohm = 4.5A. If instead you just have a big electrolytic cap with say 20mohm ESR (equivalent series resistance), then the max current can be 9V/.02ohm = 450A. The battery internal resistance will slow that down some but still it's a big number.


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