Two key technologies help the Soul EV get
the most from a full battery charge while also enabling it to function
effectively at very low temperatures. The first is a battery-heating system, using
a pair of heating pads on each two-battery module, containing elements similar
to those used in heated door mirrors. Their total power consumption is 320W,
but such is the batteries’ efficiency gain at very low temperatures that the
consumption almost pays for itself.
To
maximise the efficiency and potential range of the Soul EV, regenerative
braking captures and recycles the car’s kinetic energy while it is coasting and
braking. Users can choose between three regenerative braking modes depending on
the amount of braking support and regenerative power required.
This applies both to power usage and
recharging; the latter, on a fast charge, takes 2.5 hours with the heaters and
14 hours without when the ambient temperature is -30°C, but the difference is
minimal at a less challenging -10°C, with the charge taking about an hour
either way.
The other technology that is of interest is
the heat pump, a system already seen in the Nissan Leaf and Renault Zoe, but
given a higher output in the Soul EV. The basic model Soul EV uses positive
temperature control (PTC) semiconductors, or heat-emitting diodes, which use a
hefty 5.6kW of energy and can’t quite keep up with demands at -10°C, even
allowing for the additional heat generated by the powertrain. The heat pump in
higher-spec models uses considerably less energy yet can quickly get the cabin
up to 23°C even when it’s -10°C outside.
The
other technology that is of interest is the heat pump, a system already seen in
the Nissan Leaf and Renault Zoe, but given a higher output in the Soul EV.
The heat pump functions as a reversible
air-con system with a second condenser supplying heat to the cabin. It greatly
improves the Soul EV’s range, already reduced by 25% at 0°C compared with what
can be achieved on a summer’s day. At -25°C, the range is 50% less than in
summer, and neither of these figures includes the extra damage caused by the
need to heat the cabin. With the PTC system running flat-out, the loss can be a
further 40% of what’s left, but in the same circumstances the heat pump reduces
range by just 20%. Other HVAC refinements are maximum use of recirculated air
and separate heating zones for the driver and front passenger, with the former
getting more warm air more quickly through larger ducts.
E&Hwas one of the first to drive two
Soul EV development cars at Arjeplog – a prototype with PTC and a
pilot-production example with the heat pump. The latter was much more
welcoming, but otherwise they felt largely similar to drive with the usual
brisk step-off, unusually progressive regenerative braking, accurate steering
and handling, and a low, synthesized moan at low speeds so that pedestrians in
crowded towns and city centers can hear them coming. The same sound is relayed
through the audio speakers. An eco-button softens accelerator response and a
‘B’ position on the transmission selector boosts regenerative braking as
required.
It
will be a car for the head and for the heart, and the Soul EV embodies our
commitment to offering European customers stylish, environmentally-responsible
vehicles with an industry-leading warranty and excellent value for money.
The instruments and central display screen
are simple, with few gimmicks beyond a lushly foliated tree that grows or drops
leaves according to the driver’s eco-driving skills. The pilot car’s ESP and
traction control remained largely active even when nominally switched off. In
the prototype, however, switching the systems off led to the possibility of
amusing slides on the snow and ice. It remains to be seen how the production
EVs will behave in this respect – and whether Kia has indeed taken the lead on
range and cold weather performance.
