Battery degradation, often seen as an unavoidable consequence of electric vehicle ownership, is proving to be less of a concern than anticipated, thanks to advancements in battery technology. A recent analysis of a 2023 Volvo V90 plug-in hybrid wagon, owned for nearly four years and driven over 42,000 miles, revealed no discernible battery degradation.
Understanding the Volvo V90 PHEV Battery Test
The Volvo V90 plug-in hybrid wagon, a relatively uncommon model, was purchased by the owner partly due to its unique characteristics. The findings of this battery health assessment are expected to be relevant for all four-cylinder Volvo PHEVs manufactured since late 2022, which feature upgraded battery packs and rear electric motors on the SPA platform, including models with the Android Automotive OS infotainment system such as the S60, V60, S90, V90, XC60, and XC90.
Methodology for Battery Health Assessment
Checking the battery health of Volvo plug-in hybrids is not straightforward, lacking direct options within the infotainment system or easily accessible data via OBD dongles. The owner employed a manual method: fully draining the high-voltage battery before recharging it to capacity. This process revealed insights into why Volvo has not incorporated a manual charging limit feature in its PHEVs, unlike in many other electric vehicles where owners can set limits (e.g., 80%) to preserve long-term battery health.
For this Volvo PHEV, manual unplugging is required to stop charging before reaching 100%. However, the owner’s findings suggest this may not be necessary. Using an OBD diagnostic tool paired with a smartphone app, the owner monitored the battery pack’s state of charge and voltage as reported by the vehicle’s battery management system (BMS). This distinction is crucial, as the driver’s displayed information can differ from the BMS readings.
Analysis of Battery Performance Data
Volvo specifies a gross battery capacity of 18.8 kWh for this model, with a usable capacity of 14.9 kWh. During testing, after the range estimate in the instrument cluster reached zero and the internal combustion engine engaged, the BMS indicated a remaining state of charge of 21% with a voltage of 361 volts in Hybrid mode. In Pure mode, where more of the battery’s capacity is utilized, the engine activated at a BMS-reported state of charge of 17%, with a voltage of 357V. This confirms that even when the car indicates zero electric range, the battery still retains a reserve.
Similarly, upon reaching a full charge, indicated as 100% on the dashboard, the BMS reported an actual state of charge of 94% with a voltage of 418V. This built-in buffer, managed by the BMS, is key to maintaining long-term battery health by preventing the battery from reaching extreme charge levels. The owner noted that despite the absence of a manual charging limit, the car’s automatic management system effectively protects the battery.
Assessing Battery Degradation
Following a full charge cycle, the home charger measured 16.77 kWh of energy delivered. Accounting for an approximate 10% loss during charging, this translates to about 15 kWh of usable energy entering the battery. This figure closely aligns with Volvo’s official usable capacity of 14.9 kWh, leading to the conclusion that the battery in this Volvo V90 PHEV has experienced no degradation after nearly four years and 42,000 miles. This is particularly noteworthy given the owner’s consistent use of electric power and near-daily charging over the past nine months and 11,500 miles.
The data indicates that the BMS reserves approximately 23% of the battery’s total capacity, a significant buffer that appears to contribute to its exceptional longevity.
Future Outlook and Comparative Data
While the current results are highly positive, the owner acknowledges that future degradation is possible. However, referencing a study by Germany’s ADAC, the average Volvo PHEV retained 85% of its original battery capacity after approximately 125,000 miles (200,000 kilometers), suggesting a positive long-term outlook for this vehicle. The same study highlighted that Mercedes-Benz plug-in hybrids exhibit the least degradation, while Mitsubishi PHEVs show the most.
In terms of real-world electric range, the owner reports experiencing around 37 miles (60 km) in winter and up to 55 miles (90 km) in summer on a full charge, with a peak recorded range of 68 miles (110 km). The owner expressed satisfaction with the vehicle, citing its dual role as a luxurious family car that has significantly reduced fuel costs and offers impressive performance, suggesting the vehicle’s utility will continue for the foreseeable future.