EV LUBRICANTS
www.electrichybridvehicletechnology.com // January 2020 // 61
like copper or precious metals – things that
you see in sensors and in the windings of the
motor as well. That’s always been a
requirement to some extent, but it’s even more
important now.”
This new generation of lubricants have to
be even more versatile than before. “It has to
do all the things a traditional lubricant had
to do – very sophisticated things that have
been developed and honed for 50 years,” Banks
says. “Now we’re adding on a whole lot more
requirements as well. We’ve got to get the
friction in the clutches right, we’ve got to
protect gears, got to stop rust, and stop foam.”
The increasingly sophisticated e-axle is
another key area. “That’s where you
consolidate the diff erential, the power
electronics, the electric motor and the control
system into one compact, modular unit,” says
Banks. “That makes it very easy for people
to outsource or to have modular systems,
and that means everything is all tightly packed
in together.”
As a result, it will often be part of a one-fi ll
scenario. “There are diff erent ways of doing it,”
says Banks. “Some companies will have a glycol
system with an air gap to cool the electric
motor and oil to lubricate the gears. The
Nissan Leaf is an example of that. The next
step on from that is lubricating all of it with
an oil. Oil isn’t as good as glycol at transferring
heat, but you can apply oil directly to the
electric motor. It actually works out to be more
e cient, but applying oil directly onto a very
hot electric motor is a technological challenge.”
There is another step on from that in the
form of a multi-speed e-axle. “That’s what
we’re expecting: two or three-speed electric
transmission,” says Banks. “If you can make
an EV more e cient you can have a smaller
battery or longer range or whatever you want.
That’s the other area we’re developing for.
Whereas the hybrid transmission lubricants
are maybe more of an evolution of our existing
transmission lubricants, the e-axle area is a bit
more of a new development.”
Fluid transition
The developments don’t end there. “Actually
e-lubricants or ‘e-fl uids’ aren’t the only
domains we are looking at,” says Xavier
Branquet, global lead, OEM Group at Lubrizol.
“We are looking at electrifi cation technical
challenges, which are broad and complex,
from two perspectives: e-powertrain and
e-powerplant, or batteries, with the two
1. Lubricants protect
the inner materials
and components of an
e-motor, such as copper
used for windings
2. Electrifi cation is
presenting engine oil
and lubricant companies
with new challenges as
well as opportunities
2
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