Is Battery Swapping a Viable Option for Public Transportation EVs?

Parag Diwan
12 min readJun 19, 2018

--

After backtracking from an audacious goal of having 100% electric mobility by 2030, India’s view point is now gravitating towards attaining the target of having at least 70% of its two-wheeler /three-wheeler and public transportation stock to be in EV segment by 2030. This implies that as a nation, our focus should be on this larger segment of electric mobility which is for public good. However, to solve the charging conundrum battery swapping could be a viable option.

Battery Swapping Stations (BSS)

A type of charging infrastructure is emerging based on the premise of battery swapping. Disadvantages of conductive charging like, longer time and battery degradation in lieu of fast charging can be mitigated by using the battery swapping stations.

source: google

The adoption of EVs are hindered due to high cost of ownership. By taking out of the battery from the equation the cost can be reduce. A third party will have the ownership of the battery and will be liable for replacing the drained batteries with fresh, charged and standard ones.

Battery Swapping Stations acts as a battery aggregator and has enough clout to participate in markets for electrical energy and reserve. The BSS can maximize its profits by providing services to the system, such as voltage support, regulation reserves, or energy arbitrage.

Battery Swapping — interactions with customers, market & power system

However, battery swapping model has not fully succeeded globally due to techno-commercial dynamics. As is known, the main issues are around standardization, commercial viability and reliability.

On face of it, it seems that, in India the entire premise of ‘battery swapping’ with leasing/pay-per-use model may significantly lower the acquisition cost of the EV. Indeed, swapping may prove to be of great advantage for fleet operators, low speed EVs (e.g., taxi aggregators, e-auto, e-rickshaw etc) and busses with intercity point to point travel (< 30 km per trip, 8–10 trips per day). A well-established network of smart swappable batteries could be instrumental in rapid adoption of EVs for public transportation. However, the roadblocks still remain which are:

  • Standardization of EV Lithium Ion Battery Packs has not happened globally. The probability of this happening in India is questionable. This is so because, majority of the auto OEMs preferring to control their design strategies for battery packs as their core technology.
  • Commercially Viable Business Models, since Indian government is eschewing subsidies to create a viable non-subsidized commercially sound model is extremely important.
  • Reliability of Leased/Rented Battery Packs gets accentuated in India. In quest of achieving profitability, if battery providers short change the customer and therefore causing a potential breach may lead to a serious disaster of swapping business and can create larger controversies as well.

Advantages of Battery Swapping over Conductive or Inductive Charging

Advantages of Battery Swapping over Conductive or Inductive Charging

Concept of Battery Swapping Station

A battery swapping and charging station is an energy refueling station, where,

a. EV with depleted batteries can swap them with fully charged batteries,

b. The depleted swapped batteries are charged.

A strategically planned BSS can ensure fast swapping and extend the travel range.

To fully utilize the potential of BSS, the EV batteries should be easily replaceable and accessible to one and all. For this, there would be one most important requirement: Consistent Standardization of Batteries of various EV’s. Therefore, the best model for EV will be one where batteries will be leased by the owner from the company. The most prominent feature of this approach would be that the price of EV will drastically reduce as the cost of battery is deducted from the total vehicle cost.

Pictorial representation of Tesla EV Battery Swapping Infrastructure

Benefits of Battery Swapping System

Interaction of Station with the owner, station owner with power system

The above figure depicts the mutual interaction with all players involved, not limited to EV owner, Station owner, Power System. This inherent interdependence of the BSS and power system is significant. Following, issues related to BSS and its associated benefits are shown in with each one perspective:

Power system Perspective

EV Owner Perspective

Station Owner Perspective

Learning from Global Case-Studies

Case 1: California: Tesla Battery Swapping Stations

Tesla experimented with battery swapping technology stations in early 2013, for its pilot of 200 invitation to EV owners, only four to five came to test.

Business Model followed by Tesla

  • They setup Battery Swapping Stations at a custom-built facility at Harris Ranch in Coalinga, Calif.
  • Swapping batteries in about 90 seconds.
  • They accommodated Model S Owners driving between Los Angeles and San Francisco.
  • Drivers initially had to make an appointment to use it.

Analysis — People don’t care about pack swap and availability of free superchargers right across the street made it more difficult. According to Musk, “It is unlikely to be worthy until and unless something changes or proper awareness is being provided among people.”

Learning — Proper Awareness among people utilizing EV and Proper awareness of EV has to be floated in India for increasing its business base.

Case 2: Better Place: pioneered replacement batteries for EV in Israel & Denmark

Better place raised nearly $1 billion in Funding. It set up initially small network of BSS which allowed Israeli and Danish Electric car owners to replace spent batteries with new, charged one within a few minutes of time span. The Company predicted 100,000 EV on Israeli roads by 2010.

Business Model followed by Better place

  • Customers entered into subscriptions to purchase driving distance similar to the mobile telephone industry from which customers contract for minutes of airtime
  • The initial cost of an electric vehicle might also have been subsidized by the ongoing per-distance revenue contract just as mobile handset purchases are subsidized by per-minute mobile service contracts
  • Better Place’s goal was to enable electric cars to sell for $5,000 less than the price of the average gasoline car sold in the United States or the impact of electric cars would be minimal.

Analysis —Despite of customer satisfaction, Better Place failed to receive much with general public and didn’t have support from car manufactures. There were less than 1000 cars on road of Israel & a few hundred in Denmark. Company went to bankruptcy in 2013.

Learning — (i) Case study of innovations ahead of its time. (ii) India need to work on the difficulties of getting consumers to embrace concept of shared economy in context of batteries (iii) Perils of believing in optimistic projections

Case 3: Gogoro: Redefining urban Transformation

Gogoro developed a cloud powered battery swapping network called “Gogoro Energy Network” aiming to build an infrastructure model of power electric mobility.

Business Model followed by Gogoro:

  • A Gogoro customer who buys a vehicle gains membership access to a charging network. Rather than parking at a charging station to plug in, a scooter owner swings by a Gogoro station to swap depleted batteries for fresh ones.
  • Locating stations and reserving batteries are all performed through an app.
  • By keeping tabs on real-time battery demands, Gogoro can use algorithms to optimize where to distribute battery inventory and when to charge its batteries, taking advantage of lulls in utilities’ electricity demand to avoid paying high energy prices and over-stressing the grid.
  • The battery-share model has its challenges, including how charge capacity deteriorates over time. (This is why your smartphone runs on one charge for days when you get it and barely holds a charge by the end of its life)
  • A brand new Gogoro battery might power a scooter 100 km on a full charge; over time it may only power the scooter 80. Once it hits a certain threshold, the battery needs to be removed from circulation.

Analysis — The battery swapping model lowers the cost of scooters and reducing number of batteries in circulation benefits that can’t be replicated by on-demand charging network. For an example one tesla is building for cars.

Learning —(i) )Adoption of shared vehicles or commercial vehicles (ii) Innovation in integrating EV into energy grid, EV charging storage will become part of energy-internet

Case 5: Powerswap AB: Robotic Swap

A Swedish Startup innovated a new way for charging EV. Instead of connecting the cord or waiting on a charging station, battery is replaced with a help of robotic device within 3 minutes.

Business Model of Powerswap:

  • Technical concept was created with the goal of using the already well-established refueling infrastructure, petrol stations.
  • Powerswap handles the swap of batteries from the side, which is more optimal when it comes to automation
  • No time needed for charging; faster than filling a petrol car.
  • The car is not blocked from usage and No handling of a cord

Analysis —Taxi companies, courier services have problem with long charging stops for which this quick swapping mechanism was beneficial. Being installed at petrol stations it will not require any additional infrastructure despite of a good innovative idea, there will be no guarantees that a big financial muscle will not copy the idea. Whereas the expansion will require additional funding.

Learning — (i) The stress on the battery is significantly reduced. They charge batteries for suitable amount of time, which lowers the peaks in demand and the stress on the grid. (ii) The EV can be sold without the battery, which reduce price of an EV (less than that of a fossil fuel car). The battery will be leased and can be renewed when enhanced technology is available.

Case 5: Next Gen Battery swapping system for E-Bus at Aleees

Sufficient power is required for the operation of pure-electric bus. Unlike plug-in battery buses, it becomes important to wait for 8 hours until the battery charges completely.

Business Model of Aleees:

  • Business model requires only 6 minutes of swap.
  • Don’t affect any operational time.
  • Battery leasing and services are maintained by Aleees or any other third party.
  • No need for government infrastructure, the operators owns the swapping station.

Analysis — Taxi companies, courier services have problem with long charging stops for which this quick swapping mechanism was beneficial. Being installed at petrol stations it will not require any additional infrastructure despite of a good innovative idea, there will be no guarantees that a big financial muscle will not copy the idea. Whereas the expansion will require additional funding.

Learning — (i) We need to use the battery module swap to replenish the power to save the charging time and solve the difficulty for land acquisition required for large electric car charging stations. (ii) Eliminate unnecessary wait time. (iii) In addition to provide safe vehicles, the maintenance & repair of batteries are more important. (iv) One should provide a complete battery management and maintenance service based on the battery leasing model so that every electric bus can be safe and stable running on the streets, while providing a complete environment for battery exchange.

Battery Swapping challenges in India

As reviewed in Case studies, the main benefits of Battery Swapping is Speed. The whole operation could take less than 6 minutes. That is the same time one spend in refueling gas or petrol tanks. Another benefit is one don’t need to get tangled in dirty cords. However, the picture becomes more complex when a practical approach is implemented in India.

Advantage & challenge of Battery swapping in India

“Functionally speaking, swapping makes a compelling story but as we try and understand further, the reality may or may not fulfill the dream”.

For public transportation system, battery swapping become an essential component for fleet operators, low speed EV’s such as e-auto, e-rickshaw, buses having intercity point to point travel (< 30 Km per trip, 8–10 trips per day). Let us look into innovative frameworks that can possibly make Battery Swapping a success in India.

New and innovative ideas that could be used for implementation of charging infrastructure for Battery Swapping in India

Battery Swapping at toll stations

The main problem with EV public transportation is long driving range. Charging EV’s during a long journey is a big issue as spending 8 hour journey with 2 hour of Battery charging is not an optimum way. So, Battery Swapping comes in handy. There are more than 462 toll plazas in India, where every vehicle stops for at least 3 minutes when toll payment is done. So, Battery Swapping stations can be set up at these toll plazas and swapping can be simultaneously carried. A dedicated lane can be marked for Public transportation EVs at toll plaza needing a swap.

On Call Battery swapping

Battery can get discharge anywhere or anytime. One couldn’t even reach a Swapping station. So, one idea which can work as an innovation, are “Swapping trucks”, which come to the discharged car on the highway or city roads providing more convenience to EV consumers.

Highway Dhabas

During Long journeys, every Heavy transport vehicles rests. Most buses stop at Dhabas or Restaurants. Some space can be taken on rent near these dhabas where a swapping station may be installed. While eating or taking rest battery can be swapped with an ease.

Metro Stations and other Cluster locations

E-rickshaws and Battery operated Autos are crucial part of EV in near future. So one can locate swapping stations at metros or other transportation hubs.

Conclusion

Believing in the viability of Battery Swapping Solution specifically for public transportation buses and two/three wheelers, and Indian company, Sun Mobility is extremely gung ho about it. Led by Chetan Maini, the poster boy of India’s e-mobility story, have created automated battery swapping machines as well as developed smart light weight batteries for rapid swapping. Let us follow the journey to see how it pans out.

About the Author: Dr Parag Diwan is a noted energy professional and founder of EV Oracle, a niche consulting firm in e-mobility. <www.evoracle.com> He has built many fine institutions including the largest Energy University in India

REFERENCES:-

1. Tan, X., Sun, B., Wu, Y., & Tsang, D. (2017). Asymptotic performance evaluation of battery swapping and charging station for electric vehicles. Performance Evaluation , 1–29.

2. Yang, S., Yao, J., Kang, T., & Zhu, X. (2014). Dynamic Operation Model of the Battery Swapping Station for EV (Electric Vehicle) in Electricity Market. Energy, vol. 65, 544–549.

3. Zheng, Y., Z.Y., D., Xu, Y., Meng, K., Zhao, J., & Qiu, J. (2014). Electric Vehicle Battery Charging/Swap Stations in Distribution Systems: Comparison Study and Optimal Planning. IEEE Transactions on Power Systems, vol. 29, no. 1, 221–229.

4. Ortega-Vazquez, M., Bouffard, F., & Silva, V. (2013). Electric Vehicle Aggregator/System Operator Coordination for Charging Scheduling and Services Procurement. IEEE Transactions on Power Systems, vol. 28, no. 2, 1806–1815.

5. Kavousi-Fard, A., & Khodaei, A. (2016). Efficient Integration of Plug-in Electric Vehicles via Reconfigurable Microgrids. Energy, vol. 111, 653–663.

6. Worley, O., & Klabjan, D. (2011). Optimization of Battery Charging and Purchasing at Electric Vehicle Battery Swap Stations. IEEE Vehicle Power and Propulsion Conference (VPPC), 1–4.

7. YONEY, D. (2009, April 9). What are the benefits of charging stations vs. battery swaps vs. home charging? Retrieved from autoblog: https://www.autoblog.com/2009/04/09/greenlings-benefits-of-charging-stations-vs-battery-swaps-vs-ho/

Citations for Case Studies

1. Mohdin, A. (2015, November 07). France is reviving a failed dream: The cheap battery-swapping electric car. Retrieved from Quartz: https://qz.com/565938/france-is-reviving-a-failed-dream-the-cheap-battery-swapping-electric-car/

2. FISKE, G. (2013, may 26). Better Place files for bankruptcy. Retrieved from The Times of Israel: https://www.timesofisrael.com/better-place-files-for-bankruptcy/

3. Aleees. (2017, November 21). Battery Swapping System. Retrieved from Aleees: http://www.aleees.com/en/product/e-bus01/design/item/319.html

--

--

Parag Diwan
Parag Diwan

Written by Parag Diwan

A noted academic leader, is at the vanguard of research and curriculum design across disciplines to usher in Education.40. Evangelist & Advisor to universities