Charging station (electric bike)

from Wikipedia, the free encyclopedia
Layer model for e-bike charging infrastructure

A charging station for electric bikes is an infrastructure for charging the batteries of electric bikes (also called pedelecs or e-bikes ). Such systems are particularly important where e-bike users largely use their battery capacity over the course of a day and are dependent on recharging during the day. On the one hand, this applies to the area of cycle tourism , where refreshment stops, accommodation and sightseeing places are ideal for cycle tourists. For everyday cycling , it applies in particular to hilly / mountainous or windy environments.

Differentiation from charging stations for electric cars, basic requirements and architecture

The charging of e-bike batteries and the charging of electric vehicles differ significantly in four basic conditions:

  1. When charging electric bicycles, the amount of energy to be transferred and thus the required connection power of the charging point are considerably lower.
  2. Due to their size and weight, the batteries of electric bicycles are portable and can therefore be charged both on the bike and externally.
  3. AC charging is widespread in both vehicle categories. The charger required for this is a permanently installed component in electric cars, but an external device in electric bicycles. In contrast to electric cars, this inevitably results in an interface between the battery and charger that is accessible to the user and that is not standardized across manufacturers today. The lack of standardization of this interface and its accessibility for the user are now the causes of various dangers, problems and user annoyances when charging electric bicycles. By designing the charging stations accordingly, some of these disadvantages can be significantly counteracted.
  4. Electric bikes, their batteries and chargers are considerably easier to steal than electric cars.

These different boundary conditions mean that the charging stations for electric bicycles and for electric cars usually (should) differ significantly from one another in terms of technology and design. The layer model shown above describes the basic architecture of e-bike charging stations, although not every layer has to be implemented in real systems. The properties of a system are essentially determined by the three factors charging technology , design and installation environment (indoor / outdoor) . In detail, the following basic requirements should be taken into account for a professional e-bike charging infrastructure:

  • Fire protection
  • Electrical safety
  • battery-friendly temperature conditions
  • Theft protection
  • Usability

Charging technologies

AC charging with an external charger

Today, the charging interfaces of the e-bike batteries are mechanically and electrically not standardized across manufacturers. Therefore, for the time being, AC charging with an external personal charger is the most common charging technology, but it has some disadvantages:

  • The need to carry your own charger with you means additional luggage volume and weight for the user.
  • Since the external chargers are usually only approved for indoor use (e.g. protection class IP40) and must never get wet when it rains, many of the charging points offered outdoors today without adequate roofing are only limited by e-bike users usable.
  • Due to constant transport, mechanical loads (up to a fall) and environmental influences (moisture, rain), a charger wears out and in the worst case becomes an electrical hazard itself or no longer correctly controls the charging process, which means an increased risk of fire. Chargers should therefore be checked regularly for damage, if in doubt by experts. In the case of company charging stations for commuters, the employer can request a professional check of the charger every six months in accordance with DGUV regulation 3 , which only checks the electrical safety and not the proper functioning of the devices.

DC charging according to the energy bus standard

The disadvantages of AC charging can largely be solved by the "energy bus" standard , in which the batteries must have a uniform connector with an integrated communication interface:

  • 2 pins for supply voltage (direct voltage up to 48 V with currents up to 40A)
  • 1 pin for 12 V auxiliary voltage (for passive devices or to activate deeply discharged batteries)
  • 2 pins for CAN communication
  • Magnetic protection against polarity reversal
  • The connector can be torn off without damaging the vehicle or the charging station

The battery and the charging station exchange various data via the communication interface. a. the charging station is informed of the type of battery to be charged. This means that the charging station automatically adjusts itself to the correct charging parameters for this type of battery.

Bike energy charging station

With this charging technology, if the corresponding batteries and charging stations are available, users could forego carrying a personal charger. The "energy bus" concept would also be particularly advantageous for company charging stations for commuters, since the users here are definitely familiar with the charging technology on site, ie the personal charger can safely stay at home. However, the major e-bike manufacturers are not yet following this standard. A pilot project has taken place in the tourist region around Tegernsee, Schliersee and Achensee.

DC charging with the "bike-energy" system

The Austrian company bike energy bypasses the lack of availability of "energy-bus" -compatible batteries by using an intelligent charging cable that contains the communication electronics required for the "energy bus". Users of this system have to equip themselves with the intelligent charging cable specific to their battery type and can use it to charge their batteries according to the "energy bus" standard despite their manufacturer-specific interfaces. Where there is already a sufficiently dense network of "energy bus" -compatible charging stations, users can dispense with carrying their personal charger. There is already a notable density of stations in some cycling holiday regions, e.g. B. in the Spessart, in the Swiss holiday region Surselva or in the Salzburger Land. Where the network of such stations is even thinner, cyclists cannot do without their personal charger.

Types

Loading locker system

A distinction is made between the following four types:

The store is spatially separated from the parking

With this type of construction, charging infrastructure for a bicycle parking facility is offered compactly in one place without being assigned to specific parking spaces. Systems of this type usually consist of a matrix-like arrangement of several so-called charging lockers in which users can lock their personal charger and battery for charging in a theft-protected manner. The compartments are usually made of fire-retardant sheet steel and, depending on the model, contain one or two conventional 230 V sockets per compartment.

The advantage of this design is that the separation of charging options and parking spaces prevents the charging options of normal bicycles from being blocked. However, this design can be used to a limited extent for charging frame batteries, if

  • The compartment size is too tight for the elongated designs of removable frame batteries (one edge of the compartment base area should be at least 40 cm long)
  • the battery is permanently installed in the bicycle frame and cannot be removed for external charging. Such e-bikes cannot be charged in systems of this type.

Combined charging and parking without a bike holder

Charging point without bike holder

Systems of this type are primarily intended to retrofit one or more parking spaces in existing bicycle parking facilities with charging infrastructure. This type of construction can also be used for new systems in order to be able to combine it with bicycle mounts that are not offered in this combination from a single source.

Actually operating systems of this type without suitable bicycle mounts is not recommended, as the e-bikes are then usually not adequately protected against falling over or theft. These risks make no sense with high-quality e-bikes. To make matters worse, the batteries in particular should be protected from each fall for fire protection reasons.

Combined charging and parking with bike rack

Charging boxes with bike mounts

With this design, each bike holder is assigned a charging point - either a charging locker or an energy-bus connection.

The locker doors should advantageously have a small recess or the like so that a charging cable can be fed through the locked door to the bicycle without the risk of being crushed (charging of batteries built into the frame). The integrated bicycle mounts should provide the bicycle with good stability and protection against theft. Therefore, the brackets should be at least a leaning bracket with a knee rail, or better still, ADFC-certified or DIN79008-compliant models. In the case of row systems, a minimum distance of 70 cm between the bicycles should be observed, as the users must be able to step between the bicycles.

Combined charging and parking in a bicycle box

Bicycle box with socket

This type of construction is particularly advantageous

  • if the system is used more frequently by users with particularly high-quality e-bikes
  • in the tourist area (tourist POIs, gastronomy), where cycle tourists like to lock their bicycles together with their panniers and charge their batteries at the same time.

Even with bicycle boxes, attention should be paid to ADFC certification or conformity with DIN standard 79008, which among other things stipulates a door opening that is sufficient for most bicycles.

Construction types in primitive design (charging point only designed as a socket)

For the first three types mentioned, primitive designs are also common, which only have a 230 V socket (without locker, canopy, etc.) as a charging point. For domestic use in closed rooms, this is the widespread standard and perfectly fine if the relevant safety instructions for battery charging are also taken into account.

Primitive systems of this type, on the other hand, are to be viewed critically in public and semi-public spaces, especially at installation locations where the users do not remain within reach and sight of the charging station during the charging process (e.g. go on extensive city tours / sightseeing). There is then the risk that, in the event of a surprising change in the weather, the chargers, which are typically only intended for indoor use, will get wet and become a risk of electrical accidents or battery damage and fires due to incorrect charging parameters. This is likely to represent a foreseeable misuse within the meaning of the Product Safety Act.

  • DC Tower 1 Vienna

  • Dortmund Kleppingstrasse

  • Warnsborn estate, Arnhem

  • Brautgasse at Ulm Minster

  • Kleve-Griethausen

Installation environment (indoor / outdoor)

Charging station next to the entrance to the Parque del Buen Retiro in Madrid

The installation environment (system in a building or outdoors) has far-reaching effects on safety and user-friendliness. Outdoor systems are much less complicated in terms of fire protection than indoor systems, but they are all the more unfavorable for electrical safety and ensuring battery-friendly temperature conditions.

Common requirements for all types of charging infrastructure

The following challenges and requirements apply across the board to all types of charging infrastructure:

Fire risks

Modern e-bike batteries (usually lithium-ion batteries today) can now store around 600 watt hours of energy and thus allow ranges of between 50 and 150 kilometers, depending on driving habits. The risks of such an amount of energy stored in a small space require the user to handle them properly and are now largely controlled by intelligent battery management electronics. However, in rare cases, fires or even explosions can occur, especially when a battery is being charged

  • after mechanical damage, e.g. B. by falling
  • with a non-original or non-compatible charger
  • with a damaged charger
  • with an indoor charger that works with incorrect charging parameters due to moisture penetration
  • after a deep discharge
  • outside of the permissible charging temperature range (is usually prevented by an internal battery temperature monitor)

As rare as battery fires are, they are also difficult to control. They cannot be extinguished with water or normal fire extinguishers, only with sand or with a special metal fire extinguisher ( fire class D ). In a battery fire, poisonous gases are produced, so that people should get to safety and leave the extinguishing to the fire brigade.

Often z. E.g. in hotels or sightseeing places e-bike charging possibilities are offered in the reception area. The charging options are thus arranged in the vicinity of workplaces, so that the corresponding technical rules for workplaces ASR A2.2 must be taken into account. According to this, the workplaces concerned are to be classified as areas with increased fire risk and additional measures must be taken. One measure can be to not open the batteries in such areas, but rather to charge them in fire-retardant cabinets or lockers.

Fire protection

Battery charging stations are recommended under fire protection aspects

  • outside with sufficient distance to buildings
  • in detached garages
  • in fire-proof separated rooms
  • in underground garages

Loading lockers made of typically 2 mm thick sheet steel offer a certain degree of fire protection, although the manufacturers usually do not guarantee a fire resistance class . Charging stations may not be installed in buildings in the area of escape routes . In cases of doubt, the preventive fire protection department of the responsible fire service should be consulted.

If a serious battery problem becomes noticeable due to the development of smoke, worse can be prevented by switching off the mains voltage immediately. For this purpose, the system should have an emergency stop switch or button, which should be installed at a reasonable distance from the danger area. In publicly accessible systems, however, malefactors must always be expected who willfully operate such emergency stop switches, so that an additional indicator light is useful to draw attention to a system that has been switched off.

In hotels in particular, systems should generally also be relatively easy to implement which automatically switch off the system's mains voltage when the associated smoke detector is triggered.

Electric current hazards

The e-bike batteries themselves, with their typical voltages of up to approx. 50 V, are electrically harmless to humans. Danger from electrical current can arise from handling the chargers, which are connected to 230 V mains voltage. Currents (tingling sensation in the hand) or even life-threatening electric shocks can occur under the following circumstances :

  • Due to constant transport, mechanical stress (up to a fall) and environmental influences, a charger wears out and, in the worst case, can lose its insulating properties.
  • Handling and charging with an intact charger can also be dangerous if the charger and hands get wet at an uncovered charging point when it rains .
  • Today z. A common practice in hotels, for example, is to simply lay out a few socket strips in the bicycle storage room to connect the chargers. It is not uncommon for them to simply lie on the ground and not necessarily withstand the stress of being stepped on or being run over. It can also be dangerous if water drips from newcomers' clothes and from their bicycles onto such a power strip after a downpour.

Electrical safety

Outside charging points should have sufficient and effective roofing as rain protection so that the chargers do not get wet during the charging process itself, but also when removing them from the panniers and placing them in a locker. When dimensioning the roofing, driving rain should also be taken into account.

The entire 230 V installation of a charging infrastructure should be preceded by a residual current circuit breaker (FI switch) with a rated residual current of 10 mA or a maximum of 30 mA. The functionality of the FI switch should be tested at least every six months using the test button; this can be done by laypeople. A professional test by a qualified electrician is required at least once a year.

In general: The entire electrical installation of a charging infrastructure should only be carried out by a specialist.

Temperature problems

disadvantage: dark housing

Due to their cell construction and cell chemistry, e-bike batteries are not entirely undemanding in terms of temperatures. All manufacturers therefore specify tight temperature limits for storage, operation and charging, which should be adhered to in the interests of fire protection and service life. Most manufacturers specify an operating temperature range of −10 ... + 60 ° C and a storage temperature range of 0 ... + 30 ° C or 0 ... + 40 ° C.

For the charging process, the manufacturers specify 0 ° C or +5 ° C as the permissible minimum temperature, and values ​​between +30 ° C and +45 ° C as the maximum permissible temperature. In the case of quality batteries, internal temperature monitoring prevents the charging process if the battery temperature is outside these limits. In general, the ideal charging temperature is approximately +20 ° C.

Cold reduces the performance of a battery and the range. In winter temperatures, it is therefore advisable to insert the battery, which has been charged and stored at room temperature, into the e-bike shortly before starting the journey.

Battery-friendly temperature conditions

With charging infrastructure outdoors, ensuring the permissible storage and charging temperature ranges is not easy.

Since there are currently no heated lockers on the market, it is not possible to guarantee charging with outdoor systems at sub-zero temperatures. For the charging infrastructure at tourist destinations, this is usually not critical, given the strong seasonal nature of cycling tourism; For charging offers for everyday traffic (e.g. the daily commute), on the other hand, it represents a significant restriction.

advantageous: bright housing

In outdoor facilities, solar radiation can easily exceed the maximum permissible loading and storage temperatures. The heating up due to solar radiation is very dependent on the color of the illuminated surface: A black battery is just as disadvantageous when charging a bike as darker housing colors for charging lockers or bike boxes (even small ventilation slots can hardly improve this). White housing surfaces and very light colors such as light gray are ideal, but these are hardly offered in catalogs, especially for bicycle boxes, for reasons of susceptibility to dirt. For these reasons, system locations in the shade of buildings are ideal, or structural shading is required through light-repellent roofing and side walls.

With charging infrastructure indoors, it is much easier to ensure battery-friendly temperature conditions, but here, too, attention must be paid to proximity to heat sources or direct sunlight through windows.

Theft problems

E-bikes and also their batteries by its value a coveted loot .

But even chargers that are carried with you are at risk of theft despite their rather low value. At charging points in primitive design , they enjoy no protection whatsoever and are certainly stolen, even if it only happens as a fool's-hand . Such a loss is particularly annoying for cycle tourists and can lead to the cancellation of a cycle trip if a replacement device compatible with the battery type cannot be obtained immediately.

For this reason, bicycle parking facilities with a charging infrastructure must offer bikes, batteries and chargers equally good protection against theft.

Theft protection

For good theft protection, you should use at least leaning brackets with knee spars as bicycle mounts, or better still ADFC-certified or DIN79008-compliant models.

Lockable bicycle storage rooms or bicycle boxes (also in compliance with DIN79008 if possible) should be offered in places to stop and overnight for cycle tourists.

For both the "energy bus" and the "bike energy" charging technology, developments are in progress to combine the charging cable with a universal bike lock to form what is known as a charging lock cable. The charging lock cables should offer high-quality mechanical theft protection even without being connected to a charging station as a separate lock. When connected to an "energy bus" charging station, there is additional electronic protection in that an unauthorized disconnection of the charging connection triggers an alarm in the charging station.

User annoyance

Due to the lack of availability of their own guidelines and regulations only on the subject of "charging e-bike batteries" and the resulting laborious gathering of information, many e-bike charging stations are now largely planned and decided on the basis of manufacturer information. It is in the nature of such manufacturer information that, as a rule, it does not give a general overview of possible solutions and their advantages and disadvantages, but only focuses on their own product.

Furthermore, when planning e-bike charging stations, the fact that they are sensibly closely linked to the function of bicycle parking and that the relevant guidelines and regulations should be taken into account takes a back seat.

This can easily lead to bad planning despite the best of intentions. It therefore makes sense to involve users or experts who are familiar with user requirements, and in the case of operational parking and charging systems, also that of the works / staff council.

Usability

With the “charging spatially separated from parking” type , the bicycle parking spaces and the charging stations should not be too far apart. This also applies to the distance to lockers for locking luggage.

In the case of series systems of the type "combined charging and parking with bicycle holder" , distances of less than 70 cm between the bicycles should be avoided, as the users have to step between the bicycles, e.g. B. to use the loading locker. A compression to smaller distances between the bicycles by up / down position therefore makes no sense in such systems.

Whether you have to carry your personal charger with you or not is an important aspect of user-friendliness, especially for everyday commutes by e-bike. In this regard, "energy bus" solutions or (in the case of company parking systems) also personally assigned charging lockers, in which a personal charging device can remain permanently, are advantageous.

Guidelines, guidelines, standards

The guidelines and regulations on the subject of electromobility that are known today deal with it first and foremost with the focus on the automobile and only marginally deal with the subject of "charging e-bike batteries", which is very different in many facets.

Web links

Commons : E-bike charging stations  - collection of images, videos and audio files

Individual evidence

  1. ↑ Accident prevention regulation DGUV V3 Electrical systems and equipment . Archived from the original on December 15, 2017 ; accessed on July 26, 2018 .
  2. ↑ embedded communication blog: EnergyBus - CANopen for electric bikes. Archived from the original on December 1, 2016 ; accessed on July 31, 2018 .
  3. ↑ Charging infrastructure EnergyBus pilot project. Archived from the original on March 19, 2018 ; accessed on July 31, 2018 .
  4. ↑ E-bike charging stations in the Spessart. Archived from the original on July 26, 2018 ; accessed on July 26, 2018 .
  5. ↑ E-bike charging stations in the Surselva. Archived from the original on July 26, 2018 ; accessed on July 26, 2018 .
  6. ↑ E-bike highlights in the Salzburg region. Archived from the original on July 26, 2018 ; accessed on July 26, 2018 .
  7. ↑ a b Infoportal bicycle parking: Pros and cons. Archived from the original on June 2, 2017 ; accessed on August 1, 2018 .
  8. ↑ a b c ADFC: ADFC-recommended parking facilities. Archived from the original on September 26, 2018 ; accessed on September 26, 2018 .
  9. ↑ a b c DIN 79008-1: 2016-05: Stationary bicycle parking systems - Part 1: Requirements. Archived from the original on July 31, 2018 ; accessed on July 31, 2018 .
  10. ↑ a b VDE Association of Electrical Engineering: Compendium Li-Ion Batteries . Archived from the original on August 3, 2017 ; accessed on July 25, 2018 .
  11. ↑ Federal Institute for Occupational Safety and Health: Technical rules for workplaces - Measures against fires - ASR A2.2. Archived from the original on July 24, 2018 ; accessed on July 24, 2018 .
  12. ↑ Example: Bosch eBike Systems: PowerPack 300 | data sheets 400 | 500 PowerTube 500. Archived from the original on August 3, 2018 ; accessed on August 3, 2018 .