Vinci-HV BMS selection Selection guides | |
Guides in designing a battery with a Vinci HV BMS.
The Vinci HV is available in two topologies:.
- VinciNet: Wired to cells, wireless to Master
- VinciBus: Distributed on cells, fiber-optic to Master
This page compares the two topologies.
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Wired
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Distributed
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Description
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N+1 tap wires are connected to N cells.
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A cell board is mounted on each cell.
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General
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- Simple to understand: one box, wires.
- Few electronic assemblies
- Lots of wires
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- Safer: no high voltage wires in battery
- Few cables
- Lots of electronics
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Costs
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- Total initial BMS cost is similar
- Cheaper electronics: fewer assemblies
- More expensive wiring: lots of wires
- Cost of thermistors, beyond just a couple, escalates rapidly
- If there's a connector on the tap voltage wires, labor cost is high
- Total repair cost is similar
- Parts cost is higher: entire BMS is replaced
- Labor cost is lower: BMS is easy to access
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- Total initial BMS cost is similar
- More expensive electronics: more assemblies
- Cheaper wiring: few cables
- No additional cost for temperature measurement
- If there's a connector on the cables, labor cost is low
- Total repair cost is similar
- Parts cost is lower: single cell board or module is replaced
- Labor cost is higher: access to cell boards is harder
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Measurement accuracy
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- Inherently more immune to AC noise: filters in master
- DC errors: current in tap wires, resistance of bus bars
- Limited temperature information: few thermistors
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- Inherently more immune to DC errors: voltage is measured directly, at both cell terminals
- Careful design required for AC noise immunity
- Accurate temperature information: one thermistor per cell
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Volume, weight
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- Larger master
- Space required for lots of wires
- Practically no space required for voltage tap terminals
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- Smaller master
- Little space required for few cables
- Little space required for cell boards
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Reliability
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- Reverse or peak cell voltage beyond a certain duration will damage entire slave
- Open connection within a bank will damage entire slave (no damage if open is between banks)
- Inherently ESD proof
- If there's a connector on the tap voltage wires, lots of terminations may result in more failures
- Cell voltage tap wires may be exposed to some mechanical stress during installation; vibration during use not an issue
- Sealed slave is environmentally water-proof; connectors are not
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- Reverse or peak cell voltage, even of short duration, will damage only one cell board
- Open connection within a bank will damage only one cell board (no damage if open is between banks)
- Some ESD sensitivity
- If there's a connector on the cables, few terminations may result in fewer failures
- Cell boards may be exposed to some mechanical stress during installation, vibration during use
- Sealed cell boards and slaves are environmentally water-proof; connectors are not
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The differences between wired and distributed in the table above are independent of the BMS brand.
The table below shows differences related just to the way a Vinci BMS slave is connected.
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Wired + Wireless
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Distributed + Fiber-optic
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Slave to cells
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Wired:
13 voltage tap wires go to a bank of 12 cells.
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Fiber-optic:
Two fiber-optic cables go from a slave to the cell boards at the two ends of a bank of cells.
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Slave to master
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Wireless.
A wireless network connects the master to all the slaves.
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Parallel bus:
A 5-wire, CAN-based, VinciBus connects all the slaves and the master together.
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Isolation
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Provided by wireless network
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Provided by fiber optic cables
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Pros
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- 1 thermistor / cell
- RF immunity
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Cons
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- Only two thermistor / bank
- Possible RF interference
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- Fiber optic cables in battery
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Wired + Wireless
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Distributed + Fiber-optic
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Format
| Prismatic
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| ✔
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Pouch
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>1 battery / site
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| ✔
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1 temperature / cell
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| ✔
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