Electrical Characteristics Of Carbon - BMW i3 Technical Training Manual

I01￿General￿Vehicle￿Electronics
2.￿Voltage￿Supply
Other￿ground￿connections￿can￿also￿be￿located￿at￿the￿Drive￿module￿corresponding￿to￿the￿vehicle
equipment￿and￿national-market￿version.
In￿the￿I01￿the￿ground￿connections￿for￿the￿consumers￿cannot￿be￿connected￿to￿the￿body￿because￿of￿the
use￿of￿carbon￿for￿the￿Life￿module.￿The￿grounding￿cables￿of￿all￿consumers￿are￿connected￿to￿ground
support￿points.
The￿ground￿support￿points￿are￿located:
• Directly￿at￿the￿ground￿for￿the￿Drive￿module
• In￿the￿case￿of￿the￿Life￿module￿via￿a￿ground￿cable￿at￿a￿ground￿distribution￿block,￿which￿in￿turn￿is
connected￿to￿the￿Drive￿module.
Electrical￿characteristics￿of￿carbon
Carbon￿is￿used￿for￿the￿industrial￿manufacturing￿of￿carbon￿fibers.￿If￿these￿carbon￿fibers￿are￿also
introduced￿to￿a￿resin,￿carbon￿fiber-reinforced￿plastic,￿which￿is￿also￿referred￿to￿as￿CFRP ,￿is￿obtained.￿For
the￿sake￿of￿simplicity,￿this￿product￿is￿referred￿to￿as￿"carbon"￿in￿this￿document.
A￿differentiation￿is￿made￿between￿short￿fibers￿(0.1 – 1 mm￿long),￿long￿fibers￿(1 – 50 mm￿long)￿and
endless￿fibers￿(> 50 mm￿long).￿The￿fibers￿are￿used￿for￿different￿processing￿technologies,￿according￿to
their￿length.
The￿short￿and￿long￿fibers￿are￿suitable￿for￿fiber￿spraying.￿During￿this￿process,￿the￿fibers￿are￿sprayed
with￿a￿resin￿in￿a￿form.￿Endless￿fibers￿are￿processed￿further￿to￿obtain￿rovings￿(bundles),￿or￿other￿semi-
finished￿textile￿products￿such￿as￿woven￿fabrics.
The￿resin￿fixes￿the￿carbon￿fibers￿in￿the￿required￿arrangement￿and￿transmits￿the￿applied￿forces￿to￿and
between￿the￿fibers.￿The￿material￿carbon￿ultimately￿only￿exists￿once￿the￿carbon￿fibers￿are￿introduced
into￿the￿resin.
Structure￿of￿carbon
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