BMW I01, Информация о продукте

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I01�High-voltage�Components
5.�High-voltage�Battery�Unit
83
5.2.3.�Vent�hole
The�vent�hole�has�two�tasks.�The�first�task�of�the�vent�hole�is�to�offset�large�pressure�differences
between�the�inside�and�outside�of�the�high-voltage�battery�unit.�Such�pressure�differences�can�only
arise�in�the�event�of�a�damaged�battery�cell.�For�safety�reasons�the�housing�of�the�cell�module�with�the
damaged�battery�cell�is�opened�to�reduce�the�pressure.�The�gases�are�initially�located�in�the�housing
of�the�high-voltage�battery�unit.�From�there�they�can�be�transported�outwards�via�the�vent�hole.
The�second�task�of�the�vent�hole�is�to�transport�outwards�condensate�arising�in�the�inside�of�the�high-
voltage�battery�unit.�Besides�the�technical�components,�there�is�also�air�inside�the�high-voltage�battery
unit.�If�the�air�or�the�housing�is�cooled�by�a�lower�ambient�temperature�or�by�a�refrigerant�through�the
activation�of�the�air�conditioning�function,�some�of�the�water�vapor�from�the�air�condenses.�This�means
small�amounts�of�liquid�water�can�form�in�the�inside�of�the�high-voltage�battery�unit.�This�has�no�affect
on�the�function.�During�the�next�heating�of�the�air�or�the�housing�the�water�evaporates�again�and,�at�the
same�time,�the�pressure�in�the�housing�rises�slightly.�The�vent�hole�permits�pressure�compensation�by
allowing�the�warm�air�to�escape�outwards.�The�water�vapor�in�the�air�is�also�transported�outwards�and
also�the�previously�liquid�condensate.
To�fulfil�these�tasks�the�vent�hole�has�a�permeable�diaphragm�for�gases�(and�water�vapor)�and�an
impermeable�diaphragm�for�fluids.�There�is�a�two-piece�cover�located�above�the�diaphragm�with�which
the�diaphragm�is�protected�against�coarse�dirt�contamination.
Vent�hole
Index Explanation
1 Mounting�bolts�(x4)
2 Vent�hole
The�venting�unit�can�be�replaced�in�Service�as�an�entire�unit.�A�replacement�makes�sense�if�the
venting�unit�is�heavily�contaminated�or�has�suffered�mechanical�damage.