Toyota is working on a next-generation hybrid powertrain built around an all-new family of four-cylinder 1.5-litre engines, offered in naturally aspirated and turbocharged form. The company is targeting fuel economy more than 15% better than before. The system is also much more compact, so it can share a new platform with battery-electric and plug-in hybrid models.
Toyota has outlined a new hybrid system. It will power models built on its future ‘multi-pathway’ platforms, where battery-electric (BEV), plug-in hybrid (PHEV) and hybrid (HEV) versions share one underlying architecture. The company has not said which models will use it first or when they will arrive.
Engine and electrics designed together
Toyota has not adapted an existing engine for this system. It says the engine, hybrid system and power electronics were developed together as one integrated powertrain. The centrepiece is a new modular four-cylinder 1.5-litre engine, available with or without a turbocharger and designed for electrification from the start. According to Toyota, it is smaller and more efficient than the engines it replaces.
The naturally aspirated version is meant to cover the hybrid performance range currently served by two engines: Toyota’s 1.8-litre unit and its 1.5-litre three-cylinder. In practice, that suggests one new engine family could replace two existing ones across much of the hybrid line-up.
Toyota is pairing the new engines with lighter, more compact electric motors, power control units and inverters. The company says that integrating these parts more closely is intended to cut losses across the whole system.
Fuel economy target of more than 15%
Toyota is aiming for a fuel economy improvement of more than 15%. It says the gain should come from four sources:
- lower mechanical friction
- improved thermal management
- reduced electrical losses
- lower aerodynamic drag
The company has not yet published any power, torque, emissions or consumption figures for the new powertrain.
One platform, three powertrains
The new multi-pathway platform is primarily being developed to deliver what Toyota describes as uncompromised performance as a battery-electric vehicle. Because the new hybrid package is so compact, it can be fitted to the same platform. Toyota says hybrid and plug-in hybrid versions can use the same basic architecture without changing the vehicle’s silhouette, interior space or capability.
The lower-profile engine and hybrid unit also allow lower bonnet heights. According to Toyota, this gives designers more freedom to create sleeker, more dynamic proportions.
Economies of scale and flexible factories
Because BEV, PHEV and HEV versions will share a common architecture, Toyota can spread development and production investment across larger combined volumes. The company says this brings greater financial and engineering economies of scale without weakening any single variant.
Toyota also says the shared architecture should let its factories adjust the powertrain mix quickly to match customer demand. That matters because the pace of the shift to electric cars still varies widely from market to market.
What it means
Toyota has long argued that no single powertrain suits every market. It says energy circumstances and customer needs differ by region and country. This announcement puts that ‘multi-pathway’ strategy into hardware: one platform that can be built as an electric car, a plug-in hybrid or a conventional hybrid, depending on where and when it is sold.
Toyota says it plans to increase external sales of its new engine and hybrid technologies in the coming years, so other manufacturers may also end up using the system. The powertrain is also being developed to run on renewable and carbon-neutral fuels. Toyota presents this as a way for combustion-based electrified vehicles to keep cutting emissions while battery-electric and fuel cell technologies continue to expand.
Toyota has not yet announced which models will use the new hybrid system or when they will go on sale.
Source: newsroom.toyota.eu