POWERTRAIN
of much stricter emissions laws, is making EVs (and fuel cells) far more appealing. In addition to this, many countries have openly discussed banning diesels and sometimes all ICE engines in the long-term future, which is also facilitating the development of electrifi ed powertrains.
Q A little BMW under test Q
without causing reduced lifetime through charging specifi c ageing mechanisms (i.e lithium plating, electrode oxidisation and excessive heat generation).
IS A PERMANENT ONBOARD BATTERY DEFINITELY THE BEST SOLUTION?
The swappable battery pack idea has some benefi ts, but also has some downsides that would need to be resolved. One issue is that battery packs are far from being standardised across diff erent vehicles, and therefore it could be diffi cult to fi nd a battery pack of the same design when a replacement is required. There is also the issue of degradation, which could lead to inconsistent performance of a vehicle dependent on the current lifetime stage of the pack being swapped in, and this would be diffi cult to keep consistent without early retirement of battery packs, and the associated environmental aspects and cost.
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Battery packs are also increasingly being incorporated into the physical structure of the vehicle, which makes removing them a diffi cult task, and it may not be quicker than fast charging.
DO YOU SENSE
MORE PLUG-IN EVS OR MORE HYBRIDS IN THE FUTURE?
The industry is moving more heavily to emphasise the battery pack and reduce the infl uence of the engine,
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and therefore will gradually move from hybrids to plug-in hybrids and eventually will prioritise full EVs. The reason for this is the movements to make cities zero emission zones, and the trends for emissions decrease, which will eventually lead to emission regulations below what even hybrids can meet. This will be a gradual process however, and in the short to medium term there will still be a place for hybrid vehicles.
Legislation and incentives are really helping push EV vehicles. Particularly around the world with the zero emission zones in cities, and the implementation
They can analyse power packs up to 1,000V
HOW DO FUEL CELLS FIT INTO ALL THIS?
Fuel cells appear in a lot of
automotive roadmaps in the long- term future (post 2030) as part of fuel cell/EV hybrids. The advantage they give is that they help solve the range issues that pure EVs have, and the emissions problems that hybrids have.
They do still however require a lot of development before they can be considered in this way, not least cost. There is also still a fundamental issue of how hydrogen is created, which if from reformed methane is not environmentally sustainable. It is likely that the use of fuel cells will be on larger, long distance vehicles, with smaller city vehicles remaining electrifi ed due to the shorter-range requirements. ●
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