Overview - BMW I01 Product Information

I01￿High-voltage￿Components
5.￿High-voltage￿Battery￿Unit
The￿high-voltage￿battery￿unit￿is￿the￿energy￿storage￿device￿for￿the￿electric￿motor￿of￿the￿I01.￿It￿is￿the
equivalent￿to￿the￿fuel￿tank￿of￿a￿conventional￿vehicle￿with￿a￿combustion￿engine.￿Also￿in￿BMW￿active
hybrid￿vehicles￿there￿is￿already￿a￿high-voltage￿battery￿unit,￿which￿supplies￿the￿electric￿motor￿with
energy.￿In￿the￿BMW￿active￿hybrid￿the￿high-voltage￿battery￿is￿charged￿when￿the￿electrical￿machine￿is
operated￿as￿an￿alternator.￿This￿happens￿during￿brake￿energy￿regeneration￿or￿by￿a￿load￿point￿increase
of￿the￿combustion￿engine.￿In￿the￿I01￿the￿high-voltage￿battery￿can￿also￿be￿partially￿charged￿during
brake￿energy￿regeneration.￿However,￿it￿is￿mainly￿charged￿using￿energy￿from￿an￿external￿power
network.￿An￿optional￿range￿extender￿can￿also￿provide￿electrical￿energy￿using￿a￿gasoline￿engine￿and
another￿electrical￿machine.￿However,￿this￿is￿primarily￿used￿for￿maintaining￿the￿state￿of￿charge￿when￿the
high-voltage￿battery￿is￿already￿heavily￿discharged.￿The￿range￿of￿the￿I01￿can￿be￿increased.
5.1.￿Overview
The￿high-voltage￿battery￿of￿a￿vehicle￿with￿an￿electric￿motor￿is￿the￿equivalent￿to￿the￿fuel￿tank￿in￿a￿vehicle
with￿a￿combustion￿engine:￿It￿is￿the￿energy￿storage￿device￿for￿the￿electric￿motor.￿In￿order￿to￿achieve
the￿desired￿range￿of￿the￿I01,￿the￿amount￿of￿energy￿to￿be￿stored￿is￿correspondingly￿high,￿which￿is
why￿the￿volume￿and￿weight￿of￿the￿energy￿storage￿device￿are￿also￿high.￿Nevertheless,￿some￿vehicle
characteristics￿were￿positively￿influenced￿by￿the￿installation￿of￿the￿high-voltage￿battery￿unit￿in￿the￿Drive
module￿of￿the￿I01:
• Thanks￿to￿the￿low￿installation￿location￿the￿center￿of￿gravity￿of￿the￿vehicle￿is￿lowered,￿which
reduces￿the￿roll￿tendency￿in￿bends,￿in￿particular.
• The￿passenger￿compartment￿is￿not￿restricted￿by￿the￿high-voltage￿battery￿unit.
• The￿high-voltage￿battery￿unit￿is￿well￿accessible￿in￿Service,￿which￿reduces￿the￿repair￿costs.
5.1.1.￿Technical￿data
The￿high-voltage￿battery￿unit￿of￿the￿I01￿is￿made￿up￿of￿the￿following￿fundamental￿components:
• Cell￿modules￿with￿the￿actual￿battery￿cells
• Cell￿supervision￿circuits
• Heat￿exchanger￿with￿coolant￿ducts￿and￿heating
• Control￿unit,￿battery￿management￿electronics￿(SME)
• Wiring￿harnesses
• Safety￿box
• Connections￿(electrical,￿refrigerant,￿venting)
• Housing￿and￿fastening￿parts.
The￿battery￿cells￿are￿supplied￿by￿Samsung￿SDI￿to￿the￿BMW￿plant￿in￿Dingolfing.￿There￿the￿cell￿modules
are￿assembled￿from￿the￿battery￿cells￿and￿mounted￿into￿complete￿high-voltage￿battery￿units￿with￿the
other￿components.￿The￿manufacturer￿of￿the￿SME￿control￿unit￿and￿the￿cell￿supervision￿circuit￿is￿Preh.
The￿battery￿cells￿used￿in￿the￿high-voltage￿battery￿of￿the￿I01￿are￿lithium-ion￿cells￿(cell￿type￿NMC/LMO
mixture).￿The￿anode￿material￿of￿lithium-ion￿batteries￿is￿generally￿a￿lithium￿metal￿oxide.￿The￿designation
"NMC/LMO￿mixture"￿refers￿to￿the￿metals￿used￿for￿this￿cell￿type:￿It￿is￿a￿mix￿of￿nickel,￿manganese￿and
cobalt￿on￿the￿one￿hand,￿and￿lithium￿manganese￿oxide￿on￿the￿other￿hand.￿The￿characteristics￿of￿the
high-voltage￿battery￿for￿use￿in￿an￿electric￿vehicle￿were￿able￿to￿be￿optimized￿through￿the￿selection￿of
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