Reccommended Storage Facility Ventilation Requirements
A minimum of five air exchanges per hour in the golf car storage facility is recommended, based on historical data. The golf car storage facility ventilation system must provide adequate fresh air to prevent the hydrogen gas concentration from exceeding 2% by volume.
The Battery Gassing Flow Rate will determine the approximate hydrogen gas concentration level at any given period of time in an electric golf car storage facility. Battery gassing occurs during the charging cycle as hydrogen and oxygen are released from the battery as electric current is passed through the water in the battery cells. The flow rate is only at significant levels during the final portion of the charging cycle, and the length of this gassing period is dependant on the discharge level of the batteries. Thus, a deeper level of discharge leads to an increased length of battery gassing, with regards to time. The Club Car 48 volt electrical system has a charge finish rate of 4 amps, and a total of 24 cells. The published value for the amount of hydrogen/amp-hr per battery cell is 0.418 liters, which will be used to calculate the estimated gassing flow rate.
Charge finish rate: 4 amps
# of cells on 48V system: 24
Gassing Flow Rate = .418 liters/amp-hr-cell x 4 amps x 24 cells = 40.13 liters/hour per car
The battery gassing only occurs at this rate during the final portion of the charge cycle. Thus, depending on the depth of the discharge of the batteries, this time period will vary. As mentioned above, a deeper level of discharge leads to an increased length of battery gassing, with regards to time.
If you assume a 30 minute finish = 20 liters/car total volume
If you assume a 1 hour finish = 40 liters/car total volume
The total volume is not as important as the gassing flow rate, given that the flow rate is what will determine the gas concentration level at any given time.
Note: This flow rate is only valid for the PowerDrive 48-volt charging system which has a constant current finish and will not change as the batteries age.