BMW I01, Информация о продукте

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I01�High-voltage�Components
5.�High-voltage�Battery�Unit
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If�the�housing�of�the�high-voltage�battery�unit�is�also�damaged,�for�example�a�crack,�contact�must�be
established�with�Technical�Support�to�determine�a�suitable�course�of�action.
5.2.4.�Interface�for�the�refrigerant�circuit
It�is�incorporated�in�the�refrigerant�circuit�of�the�heating�and�air-conditioning�system�for�cooling�the
high-voltage�battery.�In�order�to�be�able�to�perform�condition-based�cooling,�there�is�an�electrically
activated�combined�expansion�and�shutoff�valve�at�the�high-voltage�battery�unit.
There�are�two�versions�of�this�valve.�Which�version�is�installed�in�the�I01�depends�on�the�equipment
without/with�heat�pump�(option 4T9).�Without�the�optional�heat�pump�the�combined�shutoff�and
expansion�valve�is�hard-wired�to�the�SME�control�unit�and�is�activated�directly�by�this�control�unit.�The
valve�is�closed�currentless,�i.e.�no�refrigerant�flows�into�the�high-voltage�battery�unit.�The�valve�only
knows�two�positions,�"closed"�and�"open".�The�amount�of�flowing�refrigerant�is�adjusted�thermally.
With�the�optional�heat�pump�the�combined�expansion�and�shutoff�valve�is�a�constantly�activated�valve.
The�precise�operating�principle�is�described�in�the�product�information�bulletin�"I01�Heating�and�Air-
Conditioning�System".
The�exact�installation�location�of�this�valve�is�shown�in�a�graphic�in�the�chapter�"Low-voltage
connections".�The�operating�principle�of�the�cooling�system�is�described�in�the�next�chapter.
5.3.�Heating�and�cooling�system
5.3.1.�Overview
To�maximizethe�service�life�of�the�high-voltage�battery�and�obtain�the�greatest�possible�power,�it�is
operated�in�a�defined�temperature�range.�The�high-voltage�battery�unit�is�essentially�operational�in
the�range�of�-40 °C�to�+50 °C.�These�temperature�limits,�however,�relate�to�the�actual�temperature
of�the�cell,�not�the�ambient�temperature.�In�terms�of�temperature�behavior�the�high-voltage�battery
unit�is�a�slow-action�system,�i.e.�it�takes�several�hours�until�the�cells�assume�the�ambient�temperature.
Therefore�having�the�battery�spend�a�short�period�of�time�in�an�extremely�hot�or�cold�environment
does�not�mean�that�the�cells�will�already�have�assumed�this�temperature.
The�optimal�range�of�the�temperature�of�the�cell�with�regard�to�service�life�and�performance�is�more
limited.�It�is�b25 °C�and�+40 °C.�Mainly�if�the�cell�temperature�is�continuously�significantly
outside�this�range�and,�at�the�same�time,�high�power�is�required,�this�would�reduce�the�service�life
of�the�battery�cells.�To�counteract�this�effect�and�ensure�maximum�performance�at�any�ambient
temperature,�there�is�automatic�heating�and�cooling�for�the�high-voltage�battery�unit�of�the�I01.
The�I01�is�equipped�as�standard�with�a�cooling�system�for�the�high-voltage�battery.�For�this�purpose
it�is�incorporated�in�the�refrigerant�circuit�of�the�heating�and�air-conditioning�system,�similar�to�current
BMW�active�hybrid�vehicles.�If�the�customer�orders�optional�equipment�494�(Seat�heating)�for�driver
and�front�passenger,�his�I01�also�has�heating�for�the�high-voltage�battery.�The�heat�effect�of�the
electrical�current�is�used�for�heating�up�the�high-voltage�battery.�This�heating�including�the�control�is
located�inside�the�high-voltage�battery�unit.�At�a�very�low�ambient�temperature�or�cell�temperature�and
with�a�connected�charging�cable,�the�heating�is�automatically�activated�if�required�in�order�to�warm�up
the�battery�cells.�This�way�the�otherwise�restricted�performance�is�improved�considerably�at�very�low
temperatures�and�the�range�can�be�increased.