Battery System Designer#

The system designer is called by the subcommand design.

Usage: python -m basd design [OPTIONS]

  system design task

Options:
  --version                       Show the version and exit.
  -v, --verbose                   Verbose information.
  -r, --requirements FILE         Read a battery system configuration from a
                                  FILE path.
  -d, --database PATH             Read a cell database from a FILE or
                                  DIRECTORY path.
  --report FILE                   Write report file to FILE.
  --max-number-of-solutions INTEGER
                                  Max. number of solutions that should be
                                  printed in the report
  -c, --cell TEXT                 Specifies used cell in the system design and
                                  additionally overrides settings
                                  (manufacturer and cell model) in
                                  requirements
  --overhead-plugin TEXT          Use a custom overhead implementation. The
                                  module needs to be installed in the same
                                  python installation/environment.
  --cores INTEGER                 Number of cpu cores used for the
                                  calculations.
  -h, --help                      Show this message and exit.

Requirements#

The requirements input is already described in the introduction (see Requirements).

Overhead Estimation#

The overhead that is generated by creating a battery system from bare batteries (i.e., by adding mounting frames, battery junction box etc.) is calculated by the overhead functionality.

The BaSD tool provides a basic implement for the overhead that is generated on

  • cell block (e.g., electrical connection to parallelize cells),

  • module (e.g., electrical connection to put cell blocks in series and create a mechanical housing for the cell blocks/cells),

  • string (e.g., electrical connection to put multiple modules in series, create a mechanical housing, and include a fuse for each particular string), and

  • pack (e.g., electrical connection to parallelize strings, create a housing for the strings, add contactors and a main fuse, the BMS etc.)

level.

The overhead can be adapted to the specific IP/knowhow of the specific designer of the battery system by providing a custom overhead plugin. The implementation of such a plugin is explained in Overhead Computation.

Report File#

The command python -m basd design [OPTIONS] creates two report files in the current working directory. One report file is saved in json format and the other one is saved in csv format. Both files contains entries/columns which can be grouped in

GENERAL#

  • Nr.: The number of the system design in the ranking

  • Manufacturer: The name of manufacturer of the used battery cell

  • Model: The model name of the used battery cell

  • Format: The cell format of the used battery cell

  • Cooling type: The cooling type which is used in the battery system design

ELECTRICAL PROPERTIES#

  • Cells in parallel: The number of cells in the system design connected in parallel

  • Cells in series: The number of cells in the system design connected in series

  • Min. cell voltage (V): Minimal allowed cell voltage

  • Max. cell voltage (V): Maximal allowed cell voltage

  • Cell capacity (Ah): Usable cell capacity

  • Voltage nom. (V): Nominal system voltage

  • Energy (Wh): System energy

  • Max. module voltage (V): Maximal module voltage

  • Min. module voltage (V): Minimal module voltage

  • Nom. module voltage (V): Nominal module voltage

  • Slave min. workload: Minimal number of cells monitored by one slave board

  • Slave max. workload: Maximal number of cells monitored by one slave board

  • Number of slaves per modules: Number of slave boards per module

MECHANICAL PROPERTIES#

  • Weight (kg): Battery system weight

  • Volume (m^3): Battery system volume

  • Length (m): Battery system length

  • Width (m): Battery system width

  • Height (m): Battery system height

SYSTEM LAYOUT#

The system layout is defined in Mechanical Overhead and Optimization Problem

  • Cell orientation: Orientation with respect to the z-axis with 0° or 90° as considered values

  • Pack z-dir: Number of strings stacked in z direction

  • Pack y-dir: Number of strings placed in a row in y direction

  • Pack x-dir: Number of strings placed in a row in x direction

  • String z-dir: Number of modules stacked in z direction

  • String y-dir: Number of modules placed in a row in y direction

  • String x-dir: Number of modules placed in a row in x direction

  • Module y-dir: Number of cell blocks placed in a row in y direction

  • Module x-dir: Number of cell blocks placed in a row in x direction

  • Cell block y-dir: Number of cells placed in a row in y direction

  • Cell block x-dir: Number of cells placed in a row in x direction

OVERHEAD#

The overhead factors are introduced in Mechanical Overhead. Volumetric and gravimetric overhead values are given as absolute values in m/kg and as relative values to the respective element in %.

  • Overhead height cell block: Height overhead of one cell block

  • Overhead height module: Height overhead of one module

  • Overhead height string: Height overhead of one string

  • Overhead height pack: Height overhead of the pack

  • Overhead length cell block: Length overhead of one cell block

  • Overhead length module: Length overhead of one module

  • Overhead length string: Length overhead of one string

  • Overhead length pack: Length overhead of the pack

  • Overhead width cell block: Width overhead of one cell block

  • Overhead width module: Width overhead of one module

  • Overhead width string: Width overhead of one string

  • Overhead width pack: Width overhead of the pack

  • Overhead weight cell block: Weight overhead of one cell block

  • Overhead weight module: Weight overhead of one module

  • Overhead weight string: Weight overhead of one string

  • Overhead weight pack: Weight overhead of of the pack