GE, Ford, University of Michigan in ARPA-E project to develop a smart, miniaturized sensing system for EV batteries; smarter BMS for longer life
03 August 2012
GE researchers, in partnership with Ford Motor Company and the University of Michigan, are developing a smart, miniaturized sensing system that has the potential to significantly extend the life of automotive traction batteries over the conventional battery systems used in electric vehicles today. The $3.1-million project is funded by the US Department of Energy’s (DOE) ARPA-E. (Earlier post.) In a separate ARPA-E-funded $3.1-million project, Ford is working with Arbin Instruments to develop a high-precision battery testing device to improve battery-life forecasting and validation.
To improve the life and reduce the lifecycle cost of EV batteries, GE will combine a novel ultra-thin battery sensor system with sophisticated modeling of cell behavior to control and optimize battery management systems. The goal of the three-year program is to demonstrate a working sensing system in an actual electric vehicle.
The car battery remains the greatest barrier and most promising opportunity to bringing EVs mainstream. Improvements in the range, cost and life of the battery will all be needed for EVs to be competitive. With better sensors and new battery analytics, we think we can make substantial progress at increasing battery life. This, in turn, could help bring down its overall cost and the cost entitlement of buying an electric car.
—Aaron Knobloch, principal investigator and mechanical engineer at GE Global Research
Today’s sensors on EVs and plug-in hybrid vehicles (PHEVs) measure the health of the battery by looking at factors such as its temperature, voltage, and current. However, these measurements provide a limited understanding of a battery’s operation and health. The goal of the ARPA-E project will be to develop small, cost-effective sensors with new measurement capabilities.
Due to their small size, these sensors will be placed in areas of the battery where existing sensor technologies cannot be currently located. The combination of small size and ability to measure new quantities will enable a much better understanding of battery performance and life.
A group of scientists from the University of Michigan, led by Anna Stefanopoulou, a professor of mechanical engineering, will use the data generated by GE sensors to verify advanced battery models. They will ultimately create schemes that use instantaneous sensor data to predict future battery-cell and battery-pack behavior.
Ensuring a battery’s health over many cycles requires taking frequent snapshots of its condition as it ages. Control systems on cars have to be able to use this vast amount of data quickly and efficiently. Information provided by advanced sensors will allow us to create and verify finely resolved physical models to underpin battery management schemes. The big challenge is to make battery management programs adapt and work fast.
—Charles Monroe, a chemical engineering professor on the University of Michigan team
The use of sensors in conjunction with real-time models will enable novel algorithms that optimize how the battery system is managed to extend its life. To demonstrate the capabilities of the sensor system and analytics, Ford will integrate them into one of their vehicles for validation.
Big data. The creation of this smart sensing platform illustrates the great potential of product development in the age of the Industrial Internet, GE noted. Every piece of industrial equipment, including batteries, generates volumes of data about its condition and operation. With the power of analytics, this data can be used to create more intelligent devices and systems that lead to improved performance for the customer.
In November 2011, GE announced an aggressive expansion of its software programs to harness big data and take industrial product development to the next level. The company has opened a global software headquarters in San Ramon, California, which will employ 400 new software professionals to support these efforts across GE’s business portfolio.
"Today’s sensors on EVs and PHEVs measure the health of the battery by looking at factors such as its temperature, voltage, and current."
So what else is there? What will the new system look at.
Maybe look at V vs, I (cell resistance) - at different current draws.
And trend it .
And mix in temperature - And trend it all.
What else?
Some automotive onboard emissions system diagnostics pull a vacuum on the vapor recovery system, seal it off and measure leak down time - OK, whatever.
So what do you do for batteries?
Posted by: ToppaTom | 03 August 2012 at 09:03 PM
And will this allow increased DoD?
Overcharging and reverse charging can obviously be prevented.
If it helps double the usable DoD, battery cost is halved.
Posted by: ToppaTom | 03 August 2012 at 09:50 PM
I doubt it will double the DOD for Lithium batteries, but it will increase it.
This would be very useful for PHEVs where the batteries are small, and they would like to use as much of the battery as possible.
If you have a 100 mile battery in an EV, you hit the limit a few times a year, if you have a 12 mile battery (in a PHEV), you probably hit the limit every day).
They may find ways of combining batteries with supercaps that further extend their lives.
It would also give a better idea of the life left in (and hence value of) a battery.
This would help establish a better market for used EVs and their batteries.
Posted by: mahonj | 04 August 2012 at 02:26 AM
DOD applies to every battery type even more so for Li-Ion.
The less energy that is drawn from a battery before topping it up again, the longer its calendar life will be. E. g. When I purchased my cell phone it was equipped with Ni-Cads. The first thing I did was to replace the batteries with NiMh. Most of the time my cell phone is located in the charging cradle. Meanwhile the batteries are over 10 years old and still going strong.
My sister has the same cell phone type and uses the same type NiMh cells as mine. In the meantime, she has the fourth set of cells in the phone because the unit is usually depleted (while carying on a conversation) and sees the cradle for charging only after the cells have been completely depleted. That is not contributable to total life.
Posted by: yoatmon | 05 August 2012 at 07:43 AM
"a smart, miniaturized sensing system that has the potential to significantly extend the life of automotive traction batteries over the conventional battery systems used in electric vehicles today. "
I'm calling marketing BS on this one. No BMS can significantly extend the life of today's packs. Smaller, cheaper BMS modules would be nice, but they aren't going to work some sort of magic.
Posted by: JRP3 | 05 August 2012 at 10:13 AM
It can only be miniaturized temp sensors inside the cells.. perhaps reporting using RFID.
Posted by: Herm | 05 August 2012 at 02:47 PM