Tram without overhead line
Target Industry
- 【Traffic】Rolling stocks / Tram / Bus
Background and Challenges
In conventional trams, it is common to use overhead wires to supply power while driving. However, overhead wire installation incurs continuous operating costs due to regular overhead wire maintenance, in addition to initial costs such as installation costs.
Reducing operating costs has become one of the major issues, and there is an increasing demand for effective utilization of regenerative energy generated during deceleration, which was disposed in the past. Another issue is the deterioration of the landscape due to the installation of overhead lines. Especially in tourist spots, there are increasing calls for the adoption of catenary-free trams.
Technical Advantages of Lithium-ion Capacitors (HSC)
Lithium-ion capacitors meet the requirements of trams such as long life, high current rate charging / discharging, and high safety. In addition, it becomes possible to utilize regenerative power effectively by installing Hybrid Super Capacitor based Energy Storage System on the trum.
Charging / Discharging with Large Current
- Our products can be charged and discharged in excess of 1000A. By adopting HSC on the power supply / charging side, it is possible to charge quickly while the train is stopped at the station. Since the HSCs can accept much higher charging current than the general Lithium Ion Batteries, it can provide higher storage efficiency of the regenerative energy.
Long Life
- Lithium-ion capacitors have extremely high cycle charge / discharge durability. Some products are durable against more than 1 million cycles of 200A CC charge / discharge (25 ° C, no rest time) conditions.
High Safety
- There is a phenomenon known as "Thermal Runaway" in Lithium Ion Batteries. This is partly due to the use of metallic lithium oxide for the positive electrode of lithium-ion batteries. Since metallic lithium oxide is not used in Hybrid Super Capacitors, "thermal runaway" does not occur in principle.
Energy Storage Device Comparison
| Hybrid Super Capacitor (HSC) | Lithium Ion Battery (LIB) | Electric Double Layer Capacitor (EDLC) | Lead-acid Battery | |
|---|---|---|---|---|
| Voltage | ◎ | ◯ | △ | △ |
| Energy density | ◯ | ◎ | △ | ◯ |
| Safety | ◯ | △ | ◯ | ◯ |
| Lifespan | ◎ | △ | ◯ | △ |