Electric power related products

Electric power related products

Charging-Discharging Controller for System

A charging-discharging converter incorporated in a system which enables reduction of energy consumption when generating electricity, by providing electricity to components when necessary, which is then accumulated when the vehicle slows down, converting kinetic energy to electrical energy.

Properties of Capacitor Charging-Discharging Controller for System manufactured by Sumitomo Wiring Systems

Charging-discharging control: The Charging-discharging cotroller we invented is made to charge and discharge efficiently against a wide change of voltage of the capacitor, by applying the two-way DCDC converter which controls the increase and decrease in pressure.
Quantity Radiation Technology: We applied the PS Board® which is a technology unique to the Sumitomo Wiring Systems , that reduces the increase of temperature of the charging-discharging controller when charging or discharging the capacitor.

Battery Wire Module for HEV

The high voltage batteries functioning as the  power source of a hybrid vehicle are a bulk material of battery cells (lithium-ion battery). Our battery wire module has a  bus bar set in the  resin case, and by assembling it to the high voltage battery, it enables the battery cells to connect in series. The dedicated terminals/harnesses are installed to detect the voltage of the battery, therefore it enables the connectors to connect with battery's ECU side.


By  consolidating the common fine components, it can be applied to high voltage batteries with different battery cell numbers. Though the bus bar set in the resin cases is bolted to the high voltage battery, the oval holes enable absorption tolerance, and improve the efficiency of the assembly work.

Compact & Lightweight Relay Box Built-In Semiconductor Fuse

We have reduced the thickness and weight of the relay box that is to be installed in the engine room, by developing a semiconductor relay module by means of the semiconductor switch which enables the relay and the FUSE function.


We are contributing to weight and thickness reduction of the electrical wires connecting to the relay box, by 50% in volume and 60% in weight in comparison with the conventional product, by converting the relays and FUSE functions into semiconductors.


The FUSE function has a control algorithm unique to the Sumitomo Wiring Systems Group, by which an exclusive custom IC automatically calculates the increase in temperature of the wires by the electricity running in the semiconductor switch, and also shuts off the electricity before it emits smoke. 

Compact And Lightweight Intelligent Power Distribution Module

Product for controlling startup of engine, headlamp relay, and wiper relay


Compact and light-weight product with interior LAN (CAN) connection function designed to make the engine compartment compact, reduce weight of the vehicle, and simplify the harness system.


・Covering to protect the part connected to wiring harnesses, and the main body
・Reducing weight through power distribution by eliminating bus bar
・Miniaturizing the structure by mounting terminals, relays and surface mounting components on the same substrate
 (compared to our old product : reduced by 20%)

Junction Box

Through incorporating parts such as relays and fuses, and by means of parts with electrical circuit integrated connection function, it provide total support to electronics control.


We aim for easily manufactured structure by modulizing components of the junction box.  The high quality junction box will be globally offered as part of the process of commonalizing vehicle components.


With the recent trend towards requiring more systems and feature for vehicles, demand for low fuel consumption and weight reduction has been increasing.  As functions required for the junction box have been increasing, weight reduction is achieved by employing the substrate for the wiring material to conduct high-density routing of the required circuit.

Power Supply BOX for HEV

High-voltage battery is installed in the hybrid vehicle (HEV) and the electric vehicle (EV) for motor driving operation. Power supply BOX for HEV is installed in the high-voltage battery, having functional parts such as relay/resistance/fuse/current sensor assembled for supply/cutoff/distribution of the high voltage power supply.


This product optimizes the layout of components such as relays for efficient circuit routing using copper-plate (called "bus bar") to achieve compact/highly integrated structure.


We are able to realize a highly reliable connection by means of the plugin connection of the bus bar (a component made by us which works to give structure to a circuit) and the connecting component used as the relay terminal for function components such as relays.