The integration of second life EV battery and vehicle-to-grid charging into a Microgrid environment by Xander Theron, uyilo e-mobility programme
Introduction What is e-mobility Storage technology within EV s What happens at end of EV battery life Second life battery process and implementation factors Second life applications in a Micro-Grid environment Vehicle-to-grid technology Vehicle-to-grid application factors
Transitions to emobility in our every day lives
Global Statistics Source: IEA The global electric car stock surpassed 2 million vehicles in 2016 after crossing the 1 million threshold in 2015 29% market share by Norway has incontestably achieved the most successful deployment China was by far the largest electric car market, accounting for more than 40% of electric cars sold worldwide India - Every car sold in India from 2030 will be electric France and Britain - No more petrol or diesel cars to be sold in the country by 2040
Global Projections Diesel car sales are declining amid government clampdowns Source: FT All Volvo cars to be electric or hybrid from 2019 Jaguar Land Rover commits to all vehicles being electric or hybrid from 2020
Unpacking Electric vehicle battery packs Battery chemistry: Lithium-Ion cells Average life expectancy of 8-10 years, OEM s use lower DOD to achieve high number of cycles EV battery packs are fitted with Battery Management system (BMS) to ensure battery operates safe and reliably Two important factors in battery status: State of charge (SoC): Level of charge stored in battery State of health (SoH): Remaining storage capacity of battery EV battery reach end of life when SoH<80%
What happens at end of life? Source: Charged EV Source: Nissan
Battery Second Life (B2L) Source: BMW Source: BMW
2 nd -life battery application factors and implementations Applying the battery packs to a secondary application has the following advantages: Reduced cost of EV ownership, the owner can now sell the old battery at the end of EV battery lifespan Business case for second life battery assessment and re-fitment Using less new batteries reducing impact of environment Battery storage could be cheaper enabling mass roll out benefiting various industries Factors to consider for second life battery applications: Second life batteries will be competing with other battery chemistries that will be first life Second life battery performance and reliability still being assessed for feasibility which can impact the value of the second life battery applications Cost of assessment and possible customized BMS fitment in the case of scaling the battery
Micro-Grids inclusive of Energy Storage Systems
The uyilo Micro-grid pilot project Solar energy generation (12kWh) Stationary second life EV battery for storage Demand side load management of charger network Individual charger load levelling Holistic energy management Reduced load onto local grid network Lower costs for grid infrastructure upgrades for EV charging
Micro-grid layout
Micro-grid layout Typical South African daily demand cycle. Source: BusinessTech 2015
2 nd -life battery application within a Micro-grid Factors to consider: Battery pack high DC bus voltage interface to the inverter and DC bus BMS functionality to the energy management system via CAN bus Specified charging philosophy Battery pack balancing SOC/battery level indication Operating environment
Vehicle-to-Grid (V2G) Source: Nissan
Vehicle-to-Home (V2H) Source: Nissan
Vehicle-to-Grid (V2G) operating models
LTE Micro-Grid with Energy Management
LTE Micro-Grid with Energy Management
Thank You * Re a leboga * Siyathokoza * Enkosi Siyabonga * Re a leboha * Ro livhuha * Ha Khensa * Dankie www.uyilo.org.za