Macquarie Uni develops new device that turns electric vehicles into charging stations

A new device developed by researchers at Australia’s Macquarie University aims to tackle the problem of what to do if faced with the awkward situation of a flat electric vehicle (EV) battery.

Running out of juice with a fossil-fuelled vehicle is not exactly convenient but has a pretty standard approach to getting out of jail – grab a jerry can and hightail it to the nearest service station or call your local roadside service for help.

Even if the 12 volt battery in your internal combustion engine (ICE) car goes flat, roadside services can get it going again and it will then recharge off your alternator if you go for a decent drive.

But the same is – currently – not as straight forward with an electric vehicle battery.

Take Dutch EV road tripper Wiebe Wakker for example, who when faced with a flat EV battery in the middle of the Australian desert, had to wait three days in searing heat until he found someone who could tow his vehicle far enough to use his converted VW Golf’s regenerative braking to add enough range to get to the next roadhouse.

Seyedfoad Taghizadeh has led a team of researchers at Macquarie University in creating a new device that lessens the inconvenience of running out of range.

Using a simple cable, a friend or family member could drive their own EV to help a stranded EV owner and “lend” enough driving range to get to the nearest public charger, or back home (we imagine the technology might also be useful for roadside services wanting to be able to assist drivers in this way also).

The bidirectional system was initially designed to assist owners of homes with batteries and would typically be installed by car makers in the EV itself, Taghizadeh tells The Driven.

“At peak hours your car could help your home,” says Taghizadeh. “You could store energy off your battery to run the appliances of your home.”

“But is also useful on the road … if you use our EV charging system then you will be able to transfer charging power from your friend or neighbour if the battery of your car becomes suddenly flat and you don’t have access to an electric vehicle charging station.”

Currently limited to single phase AC charging (the same as a standard home electric circuit), the cable uses a Type 2 plug and could be extended up to three phase.

Nissan has developed its own bidirectional charging system that is currently being used in Japan, and there are other external devices available that can be used by EV owners but that incur big costs.

According to Taghizadeh, the new device – dubbed the Intelligent Charger – is the first of its kind in that it could be used by multiple car makers to provide bidirectional charging abilities in electric vehicles.

In addition to giving electric vehicle owners an added layer of driving range confidence, the device also provides some nifty abilities that will assist the local grid, if plugged in at home.

The concept of charging many electric vehicles at home often has laypeople – and energy providers – concerned about the ability of a grid to handle the extra load.

The additional advantages of the Intelligent Charger, two ancillary functions technically known as a single-phase four-quadrant static synchronous compensator (STATCOM) and an active power filter (APF), help the performance of the grid and the quality of the power.

“When you are charging or discharging your battery, the [four-quadrant function] can improve the performance of your local grid,” says Taghizadeh.

“Also, the charger can work as an active power filter to reduce harmonics – that is, how clean the quality of your power is,” he says.

“Energy providers care about this stuff – they are worried about the performance of the grid. [But] we need to convince the utilities to provide these ancillary functions.”

“We can put these options in our chargers to if the energy providers want them.”

A third advantage is that the device can create minimum fluctuations in power when a device is turned at the local grid.

“These small tiny transients can be a disaster for the grid if there are lots of EVs plugged in. The device has minimum transient,” says Taghizadeh.

The research team is currently looking for companies interested in commercialising the device, and Taghizadeh says with the benefits to both EV owners and energy providers, some have already shown interest.