Electric Vehicle Supercharging
An electric vehicle’s power is broken down into three main sections, power delivery through slow (AC) and fast (DC) chargers, storage in the form of batteries and a battery management system (BMS) and delivery through a motor to drive the vehicle.
Petalites technology focuses on the first two aspects of this process, the power delivery through AC and DC charging systems and the Battery Management system to provide safer, faster, more reliable, and ultimately a cheaper solution to the customer and end user.
The Fastest in the Industry
Petalite’s patented SDC technology will become the 5th fundamental charging architecture to be introduced to the industry; a truly single stage isolated design with a lower part count, higher reliability, longer lifetime, wider temperature range, higher power factor and efficiency to isolated Bridge designs.
This allows electric vehicles the potential to charge at up to 460kW (920V at 500A), to compare this to traditional charging methods in the industry please refer to the graph below:
How We Compare
The comparison chart above shows that Petalite’s SDC charging technology will become the fastest for both the current industry and the next generation versions being proposed; the orange dotted line shows the point at which 15 minute charging will provide 250 miles of range. 15 minutes has become widely accepted in the industry as maximum time to which the average customer is willing to wait for their vehicle to be charged to enable mass adoption of EV’s, this is roughly comparable to a fossil fuel vehicle refuelling stop (including the detour, the queuing, the fuelling, the bathroom break and payment).
However, Petalite’s SDC technology is only limited to 460kW due to the current generation of power connector available (1000V @ 500A) and can be expanded to much higher power due to the ability of the Petalite SDC charger being easily paralleled together. This can be seen in the electrification of commuter trains where power of 750kW to 4,500kW are to be required for fast charging; Petalite are currently developing this system in partnership with Train Manufacturer Vivarail and the UK Department for Transport.
Key Hardware Advantages
• No High Voltage Aluminium Capacitors: Drastically Increases Reliability
• 4x Longer Lifetime: Estimated >600,000 hour life
• True Single Stage: No power factor correction stage required > 0.999 PF
• Wider operating temperature range
• Smaller Bill of Materials: > 30% reduction in component costs
• Low current ripple: <6% @ 300Hz (1.5% with next gen version)
• Flexible voltage ranges: 12V - 57.8V or 150V - 920V
• Isolated AC/DC Design: Efficiency to date 89% at 60V - > 94% at 920V
• Paralleled architecture: 750W – 5,000kW+
• Much lower lifetime cost: Less Downtime, Less Service
• Development path to meet CHAdeMO and CCS EV standards established
The Petalite SDC Supercharger has only one power stage on the High Voltage primary side. This battery charger is power factor corrected without the need of a Power Factor correction (PFC) pre-regulator stage. The AC current drawn from the mains is always in phase with the mains AC voltage, i.e. the power factor (cos φ) is always higher than 0,9.
A single staged battery charger means fewer components (no boost inductor, no high voltage electrolytic capacitors, no blocking diode, no PFC controller, no PFC power MOSFET) resulting to lower cost, higher reliability, higher efficiency, higher power density.
The need for rapid deployment of these battery charging systems over the next 10 years presents a logistical challenge on a global scale. Incorporating the SDC chargers in a standardised 20ft shipping container enables 1MW of charging cabibility to be installed and maintained efficiently, cost effectivly and would ideally be suited for deployments where multiple vehicles will be charged at one time.
To enable long operating lifetime and ease of service, the Petalite SDC charger modules are packaged in a standard 39U Server dimensions, this enables economies of scale, reduction in packaging costs, and faster route to market. The first generation of SDC charger are housed in a 2U server rack design and each contain 6.5 kW of charging capability. Further revisions will aim to reduce cost and increase power density to match current market leaders in the market.
Petalite's technology allows the detection of the 'cause' by analysing cell resistance and impedance up to 100 times per second, significantly faster than existing methods. The technology also learns from other deployed chargers and the history of the battery in order to charge at optimal safety levels.
SDC Supercharging Features
On-Line Impedance Measurement
Petalite’s SDC technology enables advanced battery feedback and monitoring beyond traditional sensing methods such as voltage and temperature. Significantly improving safety and performance.
Battery Condition Monitoring
Combining on-line impedance measurement with other variables allows cell level analysis at up to 100Hz, with life-cycle prediction and constant faulty cell detection faster than traditional variables i.e temperature measurement.
Lower B.O.M costs
Petalite’s SDC Supercharging technology allows the use of simplified Flyback / SDC topology up to and beyond 1kW and no high voltage aluminium electrolytic capacitors.
Longer Life hardware
Silicon carbide mosfets and zero high voltage aluminium capacitors equals a higher mean time between failure compared to traditional charging topologies.
New PCB Architecture
The hybrid Flyback / SDC architecture can be integrated into any new / existing product development cycle.
Advanced IOT integration and global connectivity enables the Petalite charging system to adapt to local environmental conditions and learn histories of other battery cells, improving safety and performance.
Battery Asset Management
Petalite’s Asset management platform combines machine learning and condition monitoring to predict residual value in battery systems throughout large deployments.
Ready to Intergrate
Petalite work with existing product design teams to incorporate the fast charging technology into your product within a minimum time frame and minimum cost for tooling.
Ready to Integrate
Petalite’s SDC Supercharging technology utilises the latest, mass produced hardware to enable rapid integration and expansion without the delays in ramping up production for specific components or materials. Below you can see an example of the algorithm running on a modified hardware system to provide a full charge in under 15 minutes.
Frequently Asked Questions
Can S.D.C Supercharging damage the cell?
SDC Supercharging allows the battery to request the maximum power based on the battery health, utilising 100% of the cell potential and not stressing the cell beyond its chemical capabilities. This is opposite to traditional charging that supply the maximum power then wait for a reaction from the cell via slow heat and voltage.
Does S.D.C Supercharging use specialist hardware?
All hardware used in the SDC Supercharging system is already being mass produced through several manufacturers, meaning that quick adoption and large scale-ups are achievable without concerns of supply chain issues. Petalite also use a license based model which means OEM’s can control their supply chain.
Is S.D.C Supercharging technology ready for integration?
Petalite’s core technology has been fully developed and tested in labs using current mass produced components. Meaning it is ready to integrate today into new and existing product lines; once agreements have been signed the typical time frame is 8-12 months for product integration, lining up with typical hardware development time scales.
What battery chemistry can be used with S.D.C Supercharging?
SDC Supercharging is able to work with the lithium-ion based family of cells for fast charging and has currently been tested on Lithium Ion cells for 15 minute charging currents. Lead Acid cells are also able to be used for cell health monitoring but will not fast charge.