I found this article which brings some information about the current sensor in the Miev:
Battery Management System Hardware Concepts: An Overview
by Markus Lelie, Thomas Braun, Marcus Knips, Hannes Nordmann, Florian Ringbeck, Hendrik Zappen and Dirk Uwe Sauer
Appl. Sci. 2018, 8, 534; doi:10.3390/app8040534 http://www.mdpi.com/journal/applsci
Here is an extract:
"The first example is the traction battery of a Mitsubishi i-MiEV (initial registration: February 2014),
shown in Figure 4a. It contains 10 Modules of eight cells and two modules with four cells, which leads
to a total amount of 88 prismatic cells, all connected serially using screwed contacts. On top of each of
the modules, a PCB is mounted, which—among other things—contains an LTC6802G-2. This IC is
designed to monitor up to 12 lithium-ion cells, which are connected in series. The same PCB design
is used for the module versions with four and eight cells. When used with four cells, the PCB is not
fully populated, as four of eight available channels are not needed. The eight-cell modules use a
second PCB to connect the second half of the module to the four remaining channels. The PCB on
top of the modules is called the Cell Management Unit (CMU) in the official service manual for the
car . In addition to voltage measurement, each PCB contains three temperature sensors, which are
connected to a controller located next to the Linear Technology BMS IC.
Apart from the cell modules, the battery housing contains contactors (separate ones for the
connection to the inverter and for DC charging), fuses, a service plug, an LEM (Freiburg im Üechtland,
Switzerland) current transducer,
an insulation monitor and a fan to extract cooling air. The service
plug splits up the pack into two sections when it is removed. In the car, it can be found below the
left hand seat. The main fuse also splits the pack in the middle. The cooling air originates from the
vehicle’s air conditioning system and is partially guided by short plastic pipes and forwarded to the
outside by the mentioned fan.
Not contained in the battery housing is the BMS master, or Battery Management Unit (BMU) ,
which communicates to the rest of the vehicle. It is located below the rear bench seat of the vehicle.
The contactors, the current transducer and the insulation monitor are connected directly to the BMU.
The CMUs on top of the cell modules are connected to each other and to the BMU via an internal CAN
bus. Some of the signals on the battery internal CAN bus can also be found on the car’s main CAN
bus in lower resolution. Compared to the smart’s battery, which is described below, there is a lot of
free space in the iMiEV’s battery housing, which may be a side effect of the air cooling."
Further in the document, we find that the sensor is a LEM CAB300 which has these specifications:
The CAB family is for battery monitoring applications where high accuracy and very low offset are required.
• Transducer using Fluxgate technology
• Zero offset
• Unlimited over-current capability
• Panel mounting
• Unipolar + 12 V battery power supply
• Ta= - 40 °C ... + 105 °C
• Accuracy (over temperature range)
• eG= Sensitivity error < 0.5 %
• et= Linearity error < 0.1 %
• Output signal: CAN.C (500 kbps)
• Optional internal digital low-pass frequency filter.
• Connector type Tyco AMP 1473672-1.
• No offset error
• High accuracy
• Low linearity error
• Full galvanic separation.
• Hybrid and electric vehicle battery pack
• Accurate current measurement for battery management applications (SOC. SOH, SOF etc.).