1. Key issues in the infrastructure of Ev
   1. The introduction of sizeable fleets of Evs will have certain infrastructure implications.
   2. Apart from electric supply industry, interested parties incl city planners (the provision of charging stations). the vehicle repair trade, the fire services. and those concerned with electric safety and technician education.
   3. the key issues are --
   4. Battery charging
      1. For small vans and car the common mode for charging will be overnight in garage. eg the normal domestic supply outlet is capable of providing 3KW for short period and 2.5kW continously.
      2. The small vehicles are of the capacity of 20-25KWh and could comfortably recharged in 8-10hrs
      3. Fleet vehicles for eg delivery vans and buses present a more difficult challenge.
      4. suppose that they are garaged and have recharging points at their parking places, the power requirement are likely to be substantial
      5. taking a fleet of 50 urban buses, each equipped with 100KWh battery capacity to be recharged btw midnight and 5am, a power supply of 1 MW be required.
      6. Such a requirment is by no means feasiable in terms of cost and engineering.
      7. The only traction batteries that are available at the acceptable cost is the lead/acid batteries.
      8. The limitation with such battery is the either battery exchange facilities or fast recharging stations
      9. An Ev which is limited to 70_80Km per day is unlikely to have wide major acceptabilty, if the journey falls within the range.
      10. the most difficult charging situation arises with single journey which are longer than the range provided
      11. the desirable time for battery recharge is preferably 15 min
      12. Recent works on rapid recharging is carried out by ALABC ( Advanced lead acid battery consortium)
      13. The goal set by ALABC to return 50,80 and 100% from depleted battery is 5,15 and 240 minutes
      14. There is another difficult with fast recharging, consider a 25KWh traction battery which is charged from 20 - 80 % and the state of charge is 15 min. Assuming no electrical losses and rate of charging is uniform, this required 60KW supply. Such a charger will be too haevy to carry on board and is likely to be costly to be dedicated to one vehicle.
   5. EV servicing
      1. Clearly the service and repair of EVs require rather different skills to those for ICEVs ie knowledge from both electrical and mech engineering, expertise in traction battery-control and maintenance and experience in dealing with high voltage system.
   6. EV road accident
      1. Paradoxically, one of the greatest danger posed by Ev may lie in the real virtues of urban use, namely silent operation.
      2. An increase in pedestrian accident is unacceptable and it may be necessary to provide some audible warning for Ev
      3. In case of a structural damage to the EVs, there are two potential hazards involved namely electrical and chemical.
      4. Rapture of the battery will present a chemical hazard. with lead/acid batteries , there would be a dangerous release of sulfuric acid and strong potassium hydroxide
   7. Battery supply/ recycling and disposal
      1. As a part for battery EV infrastructure, it is necessary to place a scheme for the recycling and disposal of the battery component.
      2. Two of the most heavy metals that are commonly employed today in the recharging of batteries, namely lead and cadium are toxic materials unsuited to waste disposal.
      3. Thus for economic and environmental reason, lead/acid and nickel cadium batteries are mostly dismantled and recycled.
      4. rechargeable lithium metal batteries are designed to operate at ambient temperature are known to present a special hazard. from this standpoint lithium-ion batteries have much better prospects.