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Bitrode Battery/Ultracapacitors Cyclers

The Energy Storage Laboratory houses many different types of bitrode battery/ultracapacitor cyclers with a range of capabilities, as shown in the table.

Bitrode Corporation's Model FTN is a life cycle test system designed to perform standard EV, standby battery, and supercapacitor tests. Designed for fast switching capability and high-speed data acquisition, the FTN is the ideal solution for demanding EV drive simulation regimes such as FUDS, SFUDS, GSFUDS, DST, ECE-15L.

NREL's Bitrode Cyclers
Cycler Number of Channels Voltage Range
(volts)
Current Range
(amps)
Bitrode - 24 3 0-24 ±100
Bitrode - 12 1 0-12 ±500
Bitrode - 36 2 0-36 ±500
Bitrode - 72 1 0-72 ±300
Bitrode - 6 1 0-6 ±200
ABC - 150 2 8-420 ±530


The ABC-150 bi-directional cycler is ideal for testing battery packs in simulated drive cycles. It has a voltage range of 8-420 volts with a maximum current output of 530 amps.

How do cyclers work?

Circuitry is designed around analog and digital controls and is driven by Bitrode's high-performance VisuaLCN software. Each FTN circuit uses a 16-bit analog-to-digital converter for high accuracy; measurement and control are designed to provide accuracy to within 0.1% of full scale. EV drive simulations require fast switching capability, and the FTN is designed with this in mind. Charge can be switched to discharge, discharge to charge, or open circuit to charge or discharge in 170 ms. One charge rate can be switched to another, or discharge to discharge, in 100 ms. Each FTN module operates from its own isolated power supply, which allows a single cell to be discharged to 0 V. This power supply isolation also enables separate cycling of multiple cells within a battery or multiple batteries within a pack.

Data in EV test environments must be acquired quickly as well; and the Bitrode driven FTN is designed to handle these requirements. When an FTN circuit is connected to a dedicated computer, test data are acquired in time increments as short as 100 ms continuously. The FTN connects to a host computer running Bitrode's VisuaLCN software for circuit control and data acquisition. This can be done on a standard Bitrode VisuaLCN network, or the FTN can communicate directly with a network PC through a standard RS232 connection.

Specifications

  • Cell voltage monitoring for cells or monoblocks
  • High resolution (±0.001 V) cell voltage monitoring
  • Thermocouple devices—Multiple temperature monitoring
  • Temperature compensation—automatically compensate charge voltage as a function of battery temperature
  • Pressure monitoring in user-specified ranges
  • Reference electrode inputs with input resistance up to 108 ohms
  • Specific gravity monitoring
  • Programmable analog or digital inputs and outputs
  • As many as 999,999 cycles per test
Photo of a three bitrode cycler.

Three Bitrode Cyclers: Each unit is capable of 0-24 V and ±100 amps.

Photo of a bitrode cycler.

Bitrode Cycler: Unit is capable of 0-12 V and ±500 amps.

Photo of a two bitrode cycler.Photo of a two bitrode cycler.

Two Bitrode Cyclers: Units are capable of 0-36 V and ±500 amps.

Photo of a bitrode cycler.

Bitrode Cycler: Unit is capable of 0-72 and ±300 amps.

Photo of a bitrode cycler.

Bitrode Cycler: Unit is capable of 0-6 Vand ±200 amps.