Epyon, a a spin-off of Delft University of Technology, provides DC charging stations and supporting network software.
One of Epyon’s electric charging patent applications is International Publication No. WO 2009/108048 (’048 Application). The ’048 Application is entitled “Electric charger for an accumulator or battery” and is directed to an electric charger for rapid charging.
The electric charger has a circuit placed on a printed circuit board (1) along with a semiconductor (2). The semiconductor (2) is located on a first part of the circuit and is thermally coupled to a heat-absorbing member or heat sink (3) via a copper track (4) such that heat from the semiconductor is transferred to the heat sink.
The heat sink (3), in turn, is in heat-conducting contact with a second part of the circuit.
According to the ’048 Application, one key to the fast-charging capability of the invention is that different thermal coupling arrangements of the heat sink to other components allow slower relinquishing of the absorbed heat:
The heat-absorbing member is therefore preferably accommodated in the electric charger such that it can absorb the heat created during charging and can then relinquish it to the surroundings in delayed manner, for which purpose a comparatively good thermal coupling of the heat-absorbing member to the heat-producing part of the circuit is preferably desirable, in addition to a relatively poor thermal coupling of the heat-absorbing member to the other parts of the circuit and the housing of the electric charger.
A related feaure of the technology is that the electric charger rapidly charges during an “on-period” but cannot be restarted during the “off-period” that follows the on-period.
According to the ’048 Application, both the off-period shutdown and the slow relinquishing of heat are “based on the insight that the development of heat occurs only during the limited on-period and that the electric charger is generally out of operation for an extended period after charging because the control means prevent a restart of the on-period.”
The ’048 Application states that, as a result of these features, the electric charger is capable of rapid charging without a significant increase in size or cost of the charger:
The invention has for its object to enable very rapid charging of an accumulator or battery, i.e. to make possible an effective charging period of several minutes without the charger having to take an appreciably larger and more expensive form than the known electric charger and without this resulting in appreciably higher costs for the charger.
In a recent guest post for Greentech Media, Mike Sherman of Chrysalix Energy Venture Capital called the acquisition of Epyon a “major milestone” in the EV charging industry and suggested it might be a tipping point because of the scale, distributions channels, and manufacturing capability of ABB.
Eric Lane is a patent attorney at Luce, Forward, Hamilton & Scripps in San Diego and the author of Green Patent Blog. Mr. Lane can be reached at email@example.com.