Battery Room Ventilation

[spenpaul]

Can u give me the formula for calculating Battery room Ventilation ? ...and what kind of material do I use for exhaust ducting to avoid corrosion.

Regards,
Paul

 

[bayoubare]

The battery area shall be ventilated, either by a natural or mechanical ventilation system, to prevent
accumulation of hydrogen. The ventilation system shall limit hydrogen accumulation to less than 2% of the
total volume of the battery area. The location should be free of areas that might collect pockets of hydrogen.
Maximum hydrogen evolution rate is 0.127 mL/s per charging ampere per cell at 25 °C and standard
pressure (760 mm Hg).8 The worst-case condition exists when forcing maximum current into a fully charged
battery.
A battery area that meets the above ventilation requirements should not be considered a classified
(hazardous) location;

 

[alehman]

It depends on the building codes. Some codes allow you to exhaust at 1 cubic foot per minute per square foot of floor area as an alternative to calculating the gassing volume.

 

[ly1phil]

Bayoubare,

Where did you get the info for the maximum hydrogen evolution rate?

Thanks,

 

[bayoubare]

IEEE 484-2002 ----5.4

 

[cherry2000]

Allowable concentration of Hydrogen varies from Code to Code. NFPA gives a value of 1%. I am attaching a spreadsheet which will help you in calculating no. of hours required to reach the dangerous concentration. Max Hydrogen evolution is readily available with Battery vendor.