Renewable Sources Of Energy For The Vehicle Engineering Essay

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Vehicle's body build brand values which also get different styles for different generation and people . Vehicle should be a perfect combination of function and apperance .

Sustainable materials should be use less energy, fewer limited resources to be made .Besides ,they do not pollute the environment and can be reused or recycled at the end of their useful life .

Renewable sources of energy for the vehicle can be wind power, solar energy ,hybrid energy ,electrical energy .

Table of contents


Globally , environmental degradation and climate change have been recognized as the main challenges that people have to overcome in the 21st century . The rapid deterioration of environment is believed to impose a severe threat on people's survival in the years ahead , if not solved effectively . In addressing global warming and greenhouse effect , this issues , countries worldwide should join forces and make a concerted effort, instead of working individually for inconsistent targets.

As we all know in December 2009 , Copenhagen Accord is a significant first step in engaging the world's largest emitters in the global effort to slash carbon emissions . Developing the low-carbon economics is promoting the sustainable human development.

Vehicle is the biggest one of the CO2 emission in our daily life, so this project is about sustainable vehicle design to explore the ultimate eco-vehicle, a solution to the various challenges the vehicle industry faces today including environmental pollution, global warming and the depletion of petroleum-based energy supplies.

As global resource limitation , developing sustainable vehicle is a major efficiency improvement for the people's future life .

To investigate the renewable energy and the material .Design issues and drivetrain concepts will allow the development of low mass, low emission. Economical vehicles that satisfy functional and safety requirements, while being amenable to disassembly and recovery of materials at end-of-life.

At the same time vehicle design is primarily concerned with developing the visual appearance and aesthetics value which combine with ergonomic functionality and utility features as well .

SEMI-DETACH is designed for future sustainable urban vehicle which explore renewable green energy with zero emission .


Sustainable energy

Sustainable energy sources of today and tomorrow are most often regarded as all renewable sources focusing on the ability of an energy source to continue providing energy, such as solar power, wind power, geothermal power and biomass .

Facing the price of oil at such high levels and increasing pressure from greenhouse effect and climate change, innovations of energy is vital for people to use green energy which provide the highest benefit for avoided environmental impacts . At same time , with the increase of government's support , renewable energy is more and more widely used in the whole world.

2008 worldwide renewable-energy sources. Source: REN21

Green energy means being environmentally friendly , lower carbon emissions and non-polluting,

Comparison with non-green sources

The Swedish utility Vattenfall did a study of full life cycle emissions of nuclear, hydro, coal, gas, solar cell, peat and wind which the utility uses to produce electricity. The net result of the study was that nuclear power produced 3.3 grams of carbon dioxide per kilowatt-hour of produced power. This compares to 400 g/(kW·h) for natural gas and 700 g/(kW·h) for coal . The study also concluded that nuclear power produced the smallest amount of CO2 of any of their electricity sources.

A 2004 article from the BBC states: "The World Health Organization (WHO) says 3 million people are killed worldwide by outdoor air pollution annually from vehicles and industrial emissions, and 1.6 million indoors through using solid fuel." In the U.S. alone, fossil fuel waste kills 20,000 people each year. A coal power plant releases 100 times as much radiation as a nuclear power plant of the same wattage. In addition, fossil fuel waste causes global warming, which leads to increased deaths from hurricanes, flooding, and other weather events. The World Nuclear Association provides a comparison of deaths due to accidents among different forms of energy production. In their comparison, deaths per TW-yr of electricity produced from 1970 to 1992 are quoted as 885 for hydropower, 342 for coal, 85 for natural gas, and 8 for nuclear.

Solar energy

Solar energy , the most abundant and fastest growing energy on Earth , is derived directly from the Sun through the form of solar radiation, increasing at 50 percent a year.

The Sun yearly delivers more than 6,000 times the energy that humans currently use. The amount of solar energy reaching the surface of the planet is so vast that in one year it is about twice as much as will ever be obtained from all of the Earth's non-renewable resources of coal, oil, natural gas, and mined uranium combined.


Solar cell

solar cell , also named photovoltaic cell , is a device that converts the energy of sunlight directly into electricity by the photovoltaic effect.


Most commercially available solar cells are capable of producing electricity for at least twenty years without a significant decrease in efficiency and The typical warranty given by panel manufacturers is for a period of 25 - 30 years, wherein the output shall not fall below 85% of the rated capacity .

Current research on solar cell

There are currently many research groups active in the field of photovoltaics around world .Developing current technology solar cells at lower cost , increasing the conversion efficiencies without an exorbitant increase in production cost and exploring new materials to serve as light absorbers and charge carriers. The ultimate goal for alternative photovoltaic concepts is to produce solar electricity at a cost comparable to currently market-dominant biomass and natural gas in order to make it the leading primary energy source.


Silicon is a very common element on the earth, One way of reducing the cost is to develop cheaper methods of obtaining silicon which is sufficiently pure. Processing silica (SiO2) to produce silicon is a very high energy process -by current technology. it takes one to two years for a conventional solar cell to generate as much energy as was used to make the silicon it contains. More energy efficient methods of synthesis are not only beneficial to the solar industry, but also to industries surrounding silicon technology as a whole.

The current industrial production of silicon is via the reaction between carbon and silica at a temperature around 1700 °C. In this process, known as carbothermic reduction, each tonne of silicon is produced with the emission of about 1.5 tonnes of carbon dioxide.

This has the interesting effect of making the cell sensitive from both the front and rear of the cell . Using this technique, one silicon wafer is enough to build a 140 watt panel, compared to about 60 wafers needed for conventional modules of same power output.

Largest Solar panel producer--China

Chinese companies have already played an important role in solar panels manufacturing in recent years. China produced solar cells/modules with an output of 1,180 MW in 2007 , according to statistics from China Photovoltaic Association.

Solar energy system in Semi-Detach

Development of a solar powered car has been an engineering goal since the 1980s.

Semi-Detach use solar panels on the fan-shaped roof for auxiliary electric system.

How ever the highest power received from the sun is radiation coming from visible light. So solar power is not available and complicated due to changes in seasons and from day to night . Energy storage is an important issue because modern energy systems usually assume continuous availability of energy. Sometimes solar cell can not receive all radiation from the sun reaching the earth because it is absorbed and dispersed due to clouds and gases within the earth's atmospheres.

As the energy solar system supplied maybe not enough for Semi-Detach to have powerful propulsion , so it use rechargeable batteries to store electricity as vehicle's main motivity .

Battery electric energy system in Semi-Detach

Semi-detach ,as electric vehicle release almost no air pollutants at the place where they are operated and provide quiet and smooth operation and consequently have less noise and vibration. . It can be finely controlled and provide high torque from rest .

Energy efficiency

Electric vehicle 'tank-to-wheels' efficiency is about a factor of 3 higher than internal combustion engine vehicles. Electric motors often achieve 90% energy conversion efficiency over the full range of speeds and power output and can be precisely controlled. They can also be combined with regenerative braking systems that have the ability to convert movement energy back into stored electricity. This can be used to reduce the wear on brake systems and reduce the total energy requirement of a trip. Regenerative braking is especially effective for start-and-stop city use.

Electric vehicles in the world

United States

The EIA's 2007 Annual Energy Review (AER) estimates the actual number of FEV's on the road in 2004 as 49,536 and a preliminary estimated 2006 number of 53,526.[51]

President Barack Obama has announced $2.4 billion for electric vehicles.[52] . $1.5 billion in grants to U.S. based manufacturers to produce highly efficient batteries and their components; up to $500 million in grants to U.S. based manufacturers to produce other components needed for electric vehicles, such as electric motors and other components;

European Union

There are measures to promote efficient vehicles in the European Parliament and of the Council of 23 April 2009 on the promotion of clean and energy-efficient road transport vehicles [61]

In Denmark petrol cars is taxed 180%+25% however EV cars (max. 2000 kg total weight) is only taxed 25%, free parking in Copenhagen and other cities, free recharging at some parking spaces.

United Kingdom

In October 2008 UK Prime Minister Gordon Brown pledged £100 million in government money to support electric, hybrid and other more environmentally friendly car projects over a five-year period to help make Britain "the European capital for electric cars" [67][70].


Many electric vehicle companies are looking to China as the leader of future electric car implementation around the world.

In April 2009, Chinese officials announced their plan to make China the world's largest producer of electric cars. Furthermore, in an attempt to design a program with incentives for buyers, Government intends to give large subsidies to buyers of electric cars; the country has almost 1.5 billion U.S. Dollars to boost the automotive industry's efforts towards modernization.

Lithium batteries have been made safe, can be recharged in minutes instead of hours, and now last longer than the typical vehicle. The production cost of these lighter, higher-capacity lithium batteries is gradually decreasing as the technology matures and production volumes increase.

Another development in lithium electrochemical cells has been the STAIR electrochemical battery. This battery could increase the capacity by 10 times compared to other similar electrochemical cells.[90]

Carbon nanotube battery

Next-Alternative Carbon Nano Tube battery pack will deliver 380 miles (610 km) range and can be recharged in less than 10 minutes.

Faster battery recharging

By soaking the matter found in conventional lithium ion batteries in a special solution, Batteries with higher capacity can be recharged 40x faster.[91] The research was conducted by Byoungwoo Kang and Gerbrand Ceder of MIT. The researchers believe the solution may appear on the market in 2011.[92]

The future of battery electric vehicles depends primarily upon the cost and availability of batteries with high energy densities, power density, and long life, as all other aspects such as motors, motor controllers, and chargers are fairly mature and cost-competitive with internal combustion engine components.


Batteries in BEVs must be periodically recharged.

BEVs most commonly charge from the power grid at home or using a street or shop recharging point

Charging time is limited primarily by the capacity of the grid connection. A normal household outlet is between 1.5 kilowatts (in the US, Canada, Japan, and other countries with 110 volt supply) to 3 kilowatts (in countries with 240 V supply).

Most people do not always require fast recharging because they have enough time, six to eight hours, during the work day or overnight to recharge. As the charging does not require attention it takes a few seconds for an owner to plug in and unplug their vehicle. Many BEV drivers prefer refueling at home, avoiding the inconvenience of visiting a fuel station. Some workplaces provide special parking bays for electric vehicles with charging equipment provided.

Charging station

Electric vehicle conversion performance depends on a number of factors including the battery chemistry:

New light lithium-ion battery-equipped EVs provide 320-480 km (200-300 mi) of range per charge.[18] Lithium is also less expensive than nickel.[19]

Finding the economic balance of range versus performance, battery capacity versus weight, and battery type versus cost challenges every EV manufacturer.

With an AC system or Advanced DC systems regenerative braking can extend range by up to 50% under extreme traffic conditions without complete stopping. Otherwise, the range is extended by about 10 to 15% in city driving.

Battery Lifespan

Individual batteries are usually arranged into large battery packs of various voltage and ampere-hour capacity products to give the required energy capacity. Battery service life should be considered when calculating the extended cost of ownership, as all batteries eventually wear out and must be replaced. The rate at which they expire depends on a number of factors.

The depth of discharge (DOD) is the recommended proportion of the total available energy storage for which that battery will achieve its rated cycles.


The safety issues of battery electric vehicles are largely dealt with by the international standard ISO 6469. This document is divided in three parts dealing with specific issues:

On-board electrical energy storage, i.e. the battery

Functional safety means and protection against failures

Protection of persons against electrical hazards.

The cathodes of early 2007 lithium-ion batteries are made from lithium-cobalt metal oxide. This material is expensive, and can release oxygen if its cell is overcharged. If the cobalt is replaced with iron phosphates, the cells will not burn or release oxygen under any charge. The price premium for early 2007 hybrids is about US $5000, some $3000 of which is for their NiMH battery packs. At early 2007 gasoline and electricity prices, that would break even after six to ten years of operation. The hybrid premium could fall to $2000 in five years, with $1200 or more of that being cost of lithium-ion batteries, providing a three-year payback.[35]

Wireless energy transfer, also known as wireless energy transmission, is the process that takes place in any system where electromagnetic energy is transmitted from a power source (such as a Tesla coil) to an electrical load, without interconnecting wires. Wireless transmission is employed in cases where interconnecting wires are inconvenient, hazardous, or impossible. Though the physics can be similar (pending on the type of wave used), there is a distinction from electromagnetic transmission for the purpose of transferring information (radio), where the amount of power transmitted is only important when it affects the integrity of the signal.

"Two coils with a matched resonance at the exact matching frequency on both ends = wireless power."

The MIT team refers to its concept as "WiTricity" (as in wireless electricity). The work will be reported in the June 7 issue of Science Express, the advance online publication of the journal Science

The key: Magnetically coupled resonance

In contrast, WiTricity is based on using coupled resonant objects. Two resonant objects of the same resonant frequency tend to exchange energy efficiently, while interacting weakly with extraneous off-resonant objects.

Using green energy

Main article: Energy storage

Main article: Grid energy storage

Renewable energy, after its generation, needs to be stored in a medium for use with autonomous devices as well as vehicles. Also, to provide household electricity in remote areas (that is areas which are not connected to the mains electricity grid), energy storage is required for use with renewable energy. Energy generation and consumption systems used in the latter case are usually stand-alone power systems.

Some examples are:

energy carriers as hydrogen, liquid nitrogen, compressed air, oxyhydrogen, batteries, to power vehicles.

flywheel energy storage, pumped-storage hydroelectricity is more usable in stationary applications (eg to power homes and offices. In household power systems, conversion of energy can also be done to reduce smell. For example organic matter such as cow dung and spoilable organic matter can be converted to biochar. To eliminate emissions, carbon capture and storage is then used.

Usually however, renewable energy is derived from the mains electricity grid. This means that energy storage is mostly not used, as the mains electricity grid is organised to produce the exact amount of energy being consumed at that particular moment. Energy production on the mains electricity grid is always set up as a combination of (large-scale) renewable energy plants, as well as other power plants as fossil-fuel power plants and nuclear power. This combination however, which is essential for this type of energy supply (as eg wind turbines, solar power plants etc.) can only produce when the wind blows and the sun shines. This is also one of the main drawbacks of the system as fossil fuel powerplants are polluting and are a main cause of global warming (nuclear power being an exception). Although fossil fuel power plants too can made emissionless (through carbon capture and storage), as well as renewable (if the plants are converted to e.g. biomass) the best solution is still to phase out the latter power plants over time. Nuclear power plants too can be more or less eliminated from their problem of nuclear waste through the use of nuclear reprocessing and newer plants as fast breeder and nuclear fusion plants.

Renewable energy power plants do provide a steady flow of energy. For example hydropower plants, ocean thermal plants, osmotic power plants all provide power at a regulated pace, and are thus available power sources at any given moment (even at night, windstill moments etc.). At present however, the number of steady-flow renewable energy plants alone is still too small to meet energy demands at the times of the day when the irregular producing renewable energy plants cannot produce power.

Besides the greening of fossil fuel and nuclear power plants, another option is the distribution and immediate use of power from solely renewable sources. In this set-up energy storage is again not necessary. For example, TREC has proposed to distribute solar power from the Sahara to Europe. Europe can distribute wind and ocean power to the Sahara and other countries. In this way, power is produced at any given time as at any point of the planet as the sun or the wind is up or ocean waves and currents are stirring. This option however is probably not possible in the short-term, as fossil fuel and nuclear power are still the main sources of energy on the mains electricity net and replacing them will not be possible overnight.

Several large-scale energy storage suggestions for the grid have been done. This improves efficiency and decreases energy losses but a conversion to a energy storing mains electricity grid is a very costly solution. Some costs could potentially be reduced by making use of energy storage equipment the consumer buys and not the state. An example is car batteries in personal vehicles that would double as an energy buffer for the electricity grid. However besides the cost, setting-up such a system would still be a very complicated and difficult procedure. Also, energy storage apparatus' as car batteries are also built with materials that pose a threat to the environment (eg sulphuric acid). The combined production of batteries for such a large part of the population would thus still not quite environmental. Besides car batteries however, other large-scale energy storage suggestions for the grid have been done which make use of less polluting energy carriers (eg compressed air tanks and flywheel energy storage).

Energy efficiency

Moving towards energy sustainability will require changes not only in the way energy is supplied, but in the way it is used, and reducing the amount of energy required to deliver various goods or services is essential. Opportunities for improvement on the demand side of the energy equation are as rich and diverse as those on the supply side, and often offer significant economic benefits.[40]

Renewable energy and energy efficiency are sometimes said to be the "twin pillars" of sustainable energy policy. Both resources must be developed in order to stabilize and reduce carbon dioxide emissions. Efficiency slows down energy demand growth so that rising clean energy supplies can make deep cuts in fossil fuel use. If energy use grows too fast, renewable energy development will chase a receding target. Likewise, unless clean energy supplies come online rapidly, slowing demand growth will only begin to reduce total emissions; reducing the carbon content of energy sources is also needed. Any serious vision of a sustainable energy economy thus requires commitments to both renewables and efficiency.[41]

Renewable energy (and energy efficiency) are no longer niche sectors that are promoted only by governments and environmentalists. The increased levels of investment and the fact that much of the capital is coming from more conventional financial actors suggest that sustainable energy options are now becoming mainstream.[42]

Climate change concerns coupled with high oil prices and increasing government support are driving increasing rates of investment in the sustainable energy industries, according to a trend analysis from the United Nations Environment Programme. According to UNEP, global investment in sustainable energy in 2007 was higher than previous levels, with $148 billion of new money raised in 2007, an increase of 60% over 2006. Total financial transactions in sustainable energy, including acquisition activity, was $204 billion.[43]

Investment flows in 2007 broadened and diversified, making the overall picture one of greater breadth and depth of sustainable energy use. The mainstream capital markets are "now fully receptive to sustainable energy companies, supported by a surge in funds destined for clean energy investment".[43]

With the concept of driving emissions-free to be sustainable, Semi-Detach explore solutions to minimize environmental impacts for achieving CO2-free mobility.

Semi-Detach develope the powertrain into two system ,one is solar energy through solar panels , the other is electric energy from lithium-ion battery . Solar energy and battery energy both drive the Semi-Detach .At the same time , project propose using the wireless energy transfer charging system to auto-charging by vehicle itself .

Semi-Detach , as the sustainable future concept car is intended for everyday use by private . The appearance is unique

It is an electrically powered vehicle and intended for everyday use by private

explore new vehicle packaging solutions and components which will be crucial to the success of the Megacity Vehicle.

The electric drive system draws its energy from new, advanced lithium-ion battery pack

They enable a range of approx. 120 kilometres in everyday use. An intelligent battery management system helps achieve this range largely independently of external climatic conditions. Additionally, the charging period required for the lithium-ion batteries is very short. On the European power grid, the battery pack can be fully charged in just 3 hours at a wall box with a current of 50 ampere at 230/240 volts.

Innovative technology without CO2 emissions.

attaches key importance to electro-mobility in the development of future-oriented vehicle concepts

developing innovative vehicle concepts for emissions-free mobility in urban areas. This so-called Megacity Vehicle will also be offered with an electrical drivetrain.

Realize this concept.

Components of the vehicle may be developed further for later integration into the Megacity Vehicle.

offers the prospect driving pleasure with emissions-free. The requirements for electro-mobility with characteristic BMW properties are being created based on ongoing development in the powertrain. It offers a high level of efficiency, power delivery, and compact construction.

The vehicle concept and drive system provide the agility and dynamic acceleration performance

The innovative character of the electric drive is also reflected in the optimized ratio between engine output and space requirements: the compact power package is fully integrated under the seat . Here the drive system occupies the space required in conventional vehicles by the differential, whose function is integrated in the drive system.

The brake system is fitted with an electric vacuum pump which is activated on demand.

The lithium-ion battery pack specially developed for this vehicle supplies energy to the motor .The high-voltage battery units offer a particularly high storage capacity and durability. storage cells are used which were developed especially for use in automobiles .

Powerful battery cells are key when it comes to designing production vehicles with electric drive. The aim is to use the best available technology in the area of energy storage as part of the development of the Megacity Vehicle.

For some time now, lithium-ion technology has demonstrated its particularly high storage capacity and deep-cycle resistance .It ensures that these properties are retained even under the special conditions of use in an automobile and the relevant demands in terms of durability, endurance and safety.

The lithium-ion batteries have their own liquid cooling system and intelligent battery management system, which are key elements in increasing both the storage capacity and the durability of the battery cells. These systems also ensure that the long range can be maintained largely independent of external climatic conditions. The high storage capacity is the decisive factor in achieving as long a range as possible. The storage system is developed to enable a real-world range of about 120 km on a single charge, depending on conditions .

Modular structure, compact construction, space-saving integration.

Another special feature of the battery pack is its outstanding compactness, despite its output and capacity. The arrangement of battery cells, grouped into several modules, is ideal in terms of packaging, functionality and vehicle balance. The battery pack replaces the combustion engine and fuel tank . Using intelligent lightweight design and the highly-efficient lithium-ion battery cells, vehicle curb weight is limited .

Reliable and safe: power electronics control and monitor vehicle functions.

The power electronics regulate the supply of electrical current to the motor at the required amperage and voltage. It also controls the supply of energy to the vehicle power network. By means of a voltage transformer and an intelligent battery management system, a reliable supply of power to all vehicle functions is ensured, including the comfort and entertainment features Drive components, energy supply, and battery pack comply with the integral safety standards for electric vehicles

Central monitoring functions integrated both in the power electronics and the battery pack ensure the continuous monitoring of all components. The driver is immediately informed of malfunctions and if necessary there is an automatic system discharge and shutdown.

Modern charging technology: fresh energy both swiftly and flexibly.

The consistent development of serial production vehicles with electric drive also includes innovative solutions for flexible, user-friendly charging of the energy storage systems in the vehicle in a way which is appropriate to everyday use. The lithium-ion battery packcan be recharged using a range of different power sources

This means that the vehicle is not dependent on a specific charging station and energy of varying power levels can be fed into the battery pack according to availability. Any conversion required is taken care of by the high-performance battery control system.

This gives the driver considerably greater flexibility in using the vehicle. In addition to using a high amperage wall box - a supply system installed in the user's home optimized to reduce charging times- it is also possible to use conventional power outlets or publicly accessible charging stations made available in co-operation with energy suppliers. In this way, stopovers can be used to extend the travel range of the vehicle when needed.

The lithium-ion batteries used in the semi-detach set a new benchmark for energy storage systems in electric vehicles. they build up a remarkably high energy capacity within a very short time.

Innovative comfort features: auxiliary heating and auxiliary air conditioning complete with remote control.

Safer, More Powerful Lithium-Ion (Li-Ion) Batteries

Li-ion batteries made with electrodes composed of lithium nickel nitride (LiNiN) to conventional Li-ion batteries containing carbon electrodes. The new materials are more efficient than the conventional electrodes and less likely to overheat, further improvements can be envisaged by changing the reaction conditions and the processing of the electrode.

In conjunction with the powerful battery technology, the concept of a purely electrically powered vehicle presents additional opportunities for the integration of innovative comfort features.

a special heating and air conditioning system was developed which is supplied with energy from the high-voltage battery via the vehicle power network. The fact that the heating system and air conditioning compressor are electrically powered means that the desired temperature can be provided inside the vehicle even when it is stationary.

The driver can heat or cool the interior before a trip using the auxiliary heating or air conditioning system - no matter whether the vehicle is connected to a charging station or the battery is fully charged.

Specific remote control functions via semi-detach

The remote control functions also provide support in searching for a nearby public charging station.

Providing sufficient charge is available,

Auto-self charging no worries for no power any more.

The driver doesn't worry to search for public charging stations in the vicinity of any given location.

well-known for its outstanding agility and efficiency. With its powerful proportions,


The distinctive appearance

also reflect the special character of this electrically powered vehicle:

In the interior, individual details highlight the distinctive style of the study and are functionally associated with the electric drive. Among other things, the interior of the semi-detach has special leather seat .

Instead of the tachometer there is a battery capacity display in the instrument panel. The current charge status of the battery pack is shown in percent. There is also a second instrument which shows how much current is being drawn from the battery as well as the amount of energy being fed back into the battery from auto charging and solar auxiliary energy .

the central information display also has a battery level indicator, an active system status display function and the positions of the nearest electric charging stations.

The focus is on the conception of a production Megacity Vehicle which fulfils the requirements of a sustainable mobility solution for urban areas, with one option being electric drive.

With its extended range of functions,the concept vehicle reflects a new approach while remaining loyal to a new future brand values. The components of the electric drive system have been designed bearing in mind the requirements of a future Megacity Vehicle so as to advance the development of a production vehicle. The semi-detach Concept is developing towards the future of an individual mobility which will combine driving pleasure with CO2-free travel.

A fully electric vehicle

Lithium-ion battery replaces the engine, transmission and fuel tank and electric motor with 125kw(170hp) sits directly behind the rear axle 160 kilometers as part of a daily routine cause no problems

In just three hours at ur home walbox or public charging station the battery is fully charged . An smartphone app keeps you ynformed about the charge condition .