Why lead and sulfuric acid?
Often buyers ask the question - are there more modern batteries on sale? Why do sellers only offer "traditional" lead-acid batteries invented back in 1859? And why did they not come to replace them with more modern nickel-cadmium, nickel-metal hydride, lithium-ion batteries? They are more capacious, they do not contain toxic acids and lead.
The answer is simple - they have disadvantages that are unacceptable for car batteries. Nickel-cadmium has a high level of self-discharge, a "memory effect" that makes it difficult to recharge, and a higher toxicity of cadmium than lead. Nickel-metal hydride has an even higher self-discharge rate. Lithium-ion batteries are explosive, expensive, and lose their charge at low temperatures. Charging a lithium-ion battery is not easy: you need a special charger that works according to a specific algorithm.
So, "in terms of the sum of indicators", it is lead-acid batteries that today remain the best option out of all possible.
Calcium or "hybrid"?
Buyers are frightened by the word "hybrid" on the battery label. And the seller cannot always explain what this "hybridity" is.
A standard battery consists of six battery "banks" connected in series in one housing. In each jar, there are alternating positive and negative electrode plates covered with a layer of active mass - the positive ones are made of lead dioxide, the negative ones are made of spongy lead. The electrodes (they are made in the form of grids) are made of a lead alloy. But pure lead is a fragile material, and therefore it is alloyed - small portions of antimony or calcium are added to the alloy.
There are practically no "pure" antimony batteries today - antimony is a catalyst for the electrolysis of water, and such a battery often "boils". To solve the boil-off problem, antimony began to be replaced with calcium.
So now the market sells either "hybrid" batteries (positive electrodes with antimony, and negative ones with calcium), or purely "calcium" (all electrodes are made of a lead-calcium alloy). The "calcium" battery has its advantages - in particular, a low level of self-discharge (loss of 50% capacity in 18-20 months) and minimal water consumption due to evaporation (1 g / Ah). However, they have a drawback - after two or three deep discharges, such a battery cannot be charged. The "hybrid" battery does not have such problems. But the consumption of water in it is one and a half to two times higher than that of "calcium" - the presence of antimony affects. And the self-discharge level is higher (loss of half the capacity in 12 months). But at the same time, "hybrid" batteries also do not require "maintenance", that is, adding distilled water to the electrolyte.
Liquid or Gel?
The battery electrodes are placed in an electrolyte, in a sulfuric acid solution. Accordingly, there are two types of batteries: with liquid electrolyte and "non-liquid" electrolyte. The most common batteries with liquid electrolyte are simpler and, accordingly, cheaper. In addition, they have enough energy reserve for all consumers in a standard car.
As for batteries with "non-liquid" electrolyte (sometimes they are all mistakenly called "gel") - the question is more complicated. Batteries, in which the electrolyte is really brought to the state of a gel with the help of silica gels, are currently used extremely rarely: only in motorcycles, and even then exclusive ones. In batteries with "non-liquid" electrolyte, all the free space between the electrodes is filled with a microporous material, which is impregnated with the electrolyte. This is AGM (Absorbed Glass Material) technology, which provides an increase in the efficiency of the active mass due to better absorption of acid, which gives a higher starting current, resistance to deep discharge, durability. It is these batteries that are best suited for vehicles with Start & Stop systems and braking energy recovery systems. But they are not "gel" ...
The market today demanded batteries with an "intermediate" technology - EFB (Enhanced Flooded Battery). It is also called "wet electrode technology". In such a battery, a kind of microfiber “envelopes” are put on the electrodes. They also retain the electrolyte, which ensures stability against cyclic discharge. But the battery itself is filled with liquid electrolyte.
Polarity - Asia or Europe?
Before offering a battery to a buyer, it is worth asking him in which country his car is assembled. Because Asian and European cars are designed for a different arrangement of terminals on the battery.
Simply put, "straight", it is "European", polarity is when, when the battery is in the "terminal closer to you" position, the positive terminal is on the left, and the negative terminal is on the right. A battery with a "reverse", that is, "Asian" polarity, is exactly the opposite. In addition, for "Europe" and "Asia", the diameter of the contact terminals may also differ. For example, on the Euro type (Type 1), the positive terminal is 19.5 mm in diameter, and the negative terminal is 17.9 mm. And in type Asia (Type 3), the "plus" has a diameter of 12.7 mm, and the "minus" - 11.1 mm. Therefore, it is still possible to install a Japanese battery on a European car (by the way, this includes "Koreans" collected in Russia): there are adapters from thin terminals to "thick" European ones.
In addition, there are several standard sizes of batteries. And it may well be that the "Asian" simply will not take a regular place due to the fact that he is less or more ...
What really matters
Sellers say: the buyer almost always does not know what he really needs. And so he has all these questions about the "calcium", "gel", "lithium-ion", "Japanese" batteries. Therefore, it is important for the seller to explain to the buyer what he wants - and why he wants exactly this!
So, the most important for the battery are three parameters.
1. Nominal electric capacity (Ah), it is determined by the energy delivered by a fully charged battery during a twenty-hour discharge. For example, the designation 6CT-60 means that the battery will deliver a current of 3 A for 20 hours and at the same time at the end the voltage at the terminals will not drop less than 10.8 V. However, this does not at all mean a linear dependence of the discharge time on the discharge current. The battery will not be able to deliver energy stably for an entire hour.
There is also an "unofficial" parameter - "reserve capacity". It is measured in minutes - how much the battery can work for itself and for the generator. For example, the reserve capacity of a car battery at a load of 25 A and a voltage drop to 10.5 V must be at least 90 minutes.
2. Nominal voltage - for a car battery it is 12 V. It can decrease when the battery is discharged and when the current is high. But experimenting by installing a battery with a higher voltage is not worth it ...
3. Cold Cranking Amperes (CCA). This parameter is especially important in Russia: it represents the amount of current that the battery can deliver at a temperature of -18 ° C for 10 seconds, with a voltage of at least 7.5 V. The higher the cold cranking current, the easier the engine will start in winter.
All these parameters are in the marking on the battery case.
What to talk to a customer about?
First of all, the seller must listen to the fact that the client has a bad light, weakly and does not spin for long, and not everyone has wires for "lighting". And only then ask:
a) How old is the car?
b) Country of origin?
c) Does the buyer drive in the winter or do they joke him in cold weather?
d) Is the vehicle equipped with Start & Stop and Brake Energy Recovery?
e) Is the car parked in the garage at night or “under the windows” in the yard?
f) Has the car been tuned, is it equipped with additional electrical equipment: heaters, non-standard lighting equipment, etc.?
g) And the most important question - how much purchase does the buyer expect?
If the buyer has an "old" or tuned car, then it is worth recommending a battery with a larger capacity, for example, instead of 50 Ah, take 55 Ah. But do not overdo it - the generators have a strictly defined capacity and it is not recommended to overload them. And to force the buyer to pay extra money is also not worth it.
If the car is an "off-road vehicle" or "SUV" and fans of country trips drive it, then they should just recommend the AGM battery. Such batteries have a rather high, up to 135%, cold cranking current, higher cycle resistance and a very high deep discharge capacity.
With the development of technology, devices are made more compact, functional and mobile. The merit of such perfection rechargeable batteries that power the device. For all the time, many different types of batteries have been invented, which have their own advantages and disadvantages.
It would seem that a promising technology a decade ago lithium ion batteries no longer meet the requirements of modern progress for mobile devices. They are not powerful enough and age quickly with frequent use or long-term storage. Since then, subtypes of lithium batteries have been developed, such as lithium iron phosphate, lithium polymer and others.
But science is not standing still and is looking for new ways to better conserve electricity. So, for example, other types of batteries are invented.
Lithium Sulfur Batteries (Li-S)
Lithium sulfuric the technology allows you to obtain batteries and an energy capacity that is twice that of their parent lithium-ion. This type of battery can be recharged up to 1500 times without significant loss in capacity. The advantage of the battery lies in the manufacturing technology and layout, which uses a liquid cathode with a sulfur content, while it is separated from the anode by a special membrane.
Lithium sulfur batteries can be used in a fairly wide temperature range, and their production cost is quite low. For mass use, it is necessary to eliminate the lack of production, namely the utilization of sulfur, which is harmful to the environment.
Magnesium Sulfur Batteries (Mg / S)
Until recently, it was not possible to combine the uses sulfur and magnesium in one cell, but not so long ago scientists were able to do this. For them to work, it was necessary to invent an electrolyte that would work with both elements.
Thanks to the invention of a new electrolyte due to the formation of crystalline particles that stabilize it. Alas, the prototype is not durable at the moment, and such batteries most likely will not go into production.
Fluoride ion batteries
To transfer charges between the cathode and the anode, such batteries use fluorine anions. This type of battery has a capacity that is tens of times higher than that of conventional lithium-ion batteries, and also boasts a lower fire hazard. The electrolyte is based on barium lanthanum.
It would seem that the development of batteries is a promising direction, but it is not without its drawbacks. A very serious obstacle to mass use is the operation of the battery only at very high temperatures.
Lithium Air Batteries (Li-O2)
Along with technological advances, mankind is already thinking about our ecology and looking for more and more clean energy sources. V lithium air In batteries, instead of metal oxides in the electrolyte, carbon is used, which reacts with air to create an electric current.
The energy density is up to 10 kWh / kg, which allows them to be used in electric vehicles and mobile devices. Expects to appear soon for the end user.
Lithium Nanophosphate Batteries
This type of battery is the next generation of lithium-ion batteries, among the advantages of which is a high charging rate and the possibility of high current efficiency. A full charge, for example, takes about 15 minutes.
The new technology of using special nano particles capable of providing a faster flow of ions makes it possible to increase the number of charge - discharge cycles by 10 times! Of course, they have a weak self-discharge and there is no memory effect. Alas, widespread use is hindered by the large weight of batteries and the need for special charging.
As a conclusion, one thing can be said. We will soon see the widespread use of electric vehicles and gadgets that can run for very long periods of time without recharging.
Electro news:
The BMW carmaker presented its version of the electric bike. The BMW electric bike is equipped with an electric motor (250 W). Acceleration up to 25 km / h.
Taking a hundred in 2.8 seconds on an electric car? The P85D update is rumored to reduce the acceleration time from 0 to 100 kilometers per hour from 3.2 to 2.8 seconds.
Spanish engineers have developed a battery that can drive more than 1000 km! It's 77% cheaper and charges in just 8 minutes
Posted date: 2011-06-29
The motivation of sales representatives is understood as the interest of a sales representative in performing certain tasks for an appropriate monetary remuneration from the employer. In other words, competent and decent motivation encourages the sales rep to do something with great zeal. As a result, after carrying out motivational events, the company remains in positive territory, develops and grows.
For the most part, a sales representative receives a salary + bonus. Motivation refers to the bonus portion of a sales rep's salary.
There are many motivational programs out there. Let's consider only the most common ones.
Percentage of export.
Decent motivation, provided the product being supplied sells well. The main thing is not to overdo it with shipments if you trade in perishable goods. Otherwise, there is a risk of getting a huge return on the delay later. Among the disadvantages of this type of motivation, one can note the low representation of the assortment on the shelves (that is, what is best sold, the sales representative fills in "tons", and, as a rule, forgets about the expansion of the assortment within the group of a certain product). Also, such motivation is not particularly beneficial if the supplier company sells its goods and additionally attracted products. A manufacturer can lose in sales of its own product if the attracted customer leaves better and faster.
As a result, the following type of motivation comes to mind.
Fulfillment of the sales plan separately for our own products and separately for borrowing.
In this situation, the sales representative has to control both the shipment of his own products and the procurement. This type of motivation, in my opinion, is most beneficial for companies that not only produce, but also sell their own products on their own (through their own staff of sales representatives).
Usually this motivation point is the main one in the bonus part and is about 40-60%.
Not all companies pay their sales representatives money to keep their accounts receivable. In my opinion, this is an oversight. It's simple. What does the law of commerce say? Commodity-money-commodity. And the more often this cycle turns around, the better for the company. It grows upward, and in breadth, and in all directions. Therefore, it is advisable to allocate about 20-25% of the bonus part to maintain accounts receivable in the norm. If a sales representative at the end of the reporting period has no overdue accounts receivable or it is minimal, it is a sin not to give him a bonus for good work.
One of the most useful motivations from an employer. The logic is simple - the more part of the market a company covers, the more significant player it becomes in the eyes of its potential suppliers of new attracted products. Accordingly, large companies can dictate their terms to suppliers and beat out the best conditions and prices for themselves.
Motivate sales representatives to open new outlets in a variety of ways. Someone pays a certain amount for each new point. But this is not entirely correct in relation to different sales representatives. Indeed, one merchant has an active client base (ACB) of 50 outlets, while the other has 100. Employment varies slightly, you must agree. Therefore, it is more expedient to allocate the same 20-25% of the bonus part for the development of the client base and provide each sales representative with an individual plan for opening new outlets.
It is useful to alternate motivational programs from time to time. This does not apply except for the fulfillment of the shipping plan. The shipment plan, by the way, is usually always increased in relation to the fact of exportation of the previous month. Depending on the season (if the product has such a dependence), the plan is increased from 10 (for especially distinguished sales representatives) to 40 (for those who “failed” the plan of the last month)%. All this is necessary for the growth of the company, so that it does not stagnate in one place.
Sales representative efficiency (COP).
This motivation does not apply to the ratio of the number of orders divided by the number of visits. Here, efficiency means the following.
Let's say there is a "own" product and attracted products. There can be several groups of goods in "own" product. The attraction is the same, plus there may be several different suppliers. The company is interested in having the entire range of products supplied by it at each point of sale. Ideally, 100% efficiency will be when all points are loaded within a month by all groups of goods and suppliers (attracted). For a number of reasons, this practically cannot happen if you have more than 50 retail outlets with a joint stock bank. But you need to strive for this. There is no limit to perfection.
Sales representatives may be motivated for efficiency as follows. The ideal (100%) is the best efficiency indicator for the entire company for the previous month (for example, this is 70% of the maximum possible). Based on the results of the current month, a verdict is made on who gets into this bonus. You can set a minimum threshold (for example, from 80-90% of the best result of the last month, the bonus is paid).
A very powerful motivation. Tested many times on our own experience.
Motivation from the manufacturer and from the attracted products.
And today we will talk about the imaginary ones - with a gigantic specific capacity and instant charging. News of such developments appears with enviable regularity, but the future has not yet arrived, and we still use the lithium-ion batteries that appeared at the beginning of the decade before last, or their slightly more advanced lithium-polymer analogues. So what's the matter, technological difficulties, misinterpretation of scientists' words, or something else? Let's try to figure it out.
Chasing charging speed
One of the battery parameters that scientists and large companies are constantly trying to improve is charging speed. However, it will not be possible to increase it infinitely not even due to the chemical laws of the reactions occurring in batteries (especially since the developers of aluminum-ion batteries have already stated that this type of battery can be fully charged in just a second), but because of physical limitations. Suppose we have a smartphone with a 3000 mAh battery and support for fast charging. You can fully charge such a gadget within an hour with an average current of 3 A (on average, because the voltage changes during charging). However, if we want to get a full charge in just one minute, we need a current strength of 180 A without taking into account various losses. To charge the device with such a current, you will need a wire with a diameter of about 9 mm - twice as thick as the smartphone itself. Yes, and a current of 180 A at a voltage of about 5 V, a conventional charger will not be able to give out: owners of smartphones will need a pulse current converter like the one shown in the photo below.
An alternative to increasing the amperage is to increase the voltage. But it is, as a rule, fixed, and for lithium-ion batteries it is 3.7 V. Of course, it can be exceeded - charging using Quick Charge 3.0 technology comes with a voltage of up to 20 V, but an attempt to charge the battery with a voltage of about 220 V is useless will not lead to good, and it is not possible to solve this problem in the near future. Modern batteries simply cannot use this voltage.
Eternal accumulators
Of course, now we are not talking about a "perpetual motion machine", but about batteries with a long service life. Modern lithium-ion batteries for smartphones can withstand a maximum of a couple of years of active use of devices, after which their capacity is steadily decreasing. Owners of smartphones with removable batteries are a little more fortunate than others, but in this case it is worth making sure that the battery was produced recently: lithium-ion batteries degrade even when not in use.
Scientists at Stanford University proposed their solution to this problem: to cover the electrodes of existing types of lithium-ion batteries with a polymer material with the addition of graphite nanoparticles. According to the idea of scientists, this will protect the electrodes, which inevitably become covered with microcracks during operation, and the same microcracks in the polymer material will heal on their own. The principle of this material is similar to the technology used in the LG G Flex smartphone with a self-healing back cover.
Transition to the third dimension
In 2013, it was reported that researchers at the University of Illinois were developing a new type of lithium-ion batteries. Scientists stated that the specific power of such batteries will be up to 1000 mW / (cm * mm), while the specific power of conventional lithium-ion batteries ranges between 10-100 mW / (cm * mm). We used just such units of measurement, since we are talking about rather small structures with a thickness of tens of nanometers.
Instead of the flat anode and cathode used in traditional Li-Ion batteries, the scientists proposed using three-dimensional structures: a crystal lattice of nickel sulfide on porous nickel as an anode and lithium manganese dioxide on porous nickel as a cathode.
Despite all the doubts caused by the lack of the exact parameters of the new batteries in the first press releases, as well as the prototypes that have not yet been presented, the new type of batteries is still real. This is confirmed by several scientific articles on this topic, published over the past two years. However, if such batteries become available to end users, this will be very long ago.
Charging through the screen
Scientists and engineers are trying to extend the life of our gadgets not only by searching for new types of batteries or increasing their energy efficiency, but also in rather unusual ways. Michigan State University researchers have proposed embedding transparent solar panels directly into a screen. Since the principle of operation of such panels is based on the absorption of solar radiation by them, in order to make them transparent, scientists had to go for a trick: the material of the panels of a new type absorbs only invisible radiation (infrared and ultraviolet), after which photons, reflected from the wide edges of the glass, are absorbed by narrow stripes solar panels of the traditional type, located along its edges.
The main obstacle to the introduction of such technology is the low efficiency of such panels - only 1% against 25% of traditional solar panels. Now scientists are looking for ways to increase efficiency by at least 5%, but a quick solution to this problem can hardly be expected. By the way, a similar technology was recently patented by Apple, but it is not yet known where exactly the manufacturer will place solar panels in its devices.
Before that, we meant a rechargeable battery under the words "battery" and "accumulator", but some researchers believe that disposable voltage sources can be used in gadgets. As batteries that could work without recharging or other maintenance for several years (or even several decades), scientists at the University of Missouri proposed using RTGs - radioisotope thermoelectric generators. The principle of operation of the RTG is based on the conversion of heat released during radio decay into electricity. Many such installations are known for their use in space and hard-to-reach places on Earth, but in the United States, miniature radioisotope batteries were also used in pacemakers.
Work on an improved type of such batteries has been going on since 2009, and even prototypes of such batteries have been shown. But we will not be able to see radioisotope batteries in smartphones in the near future: they are expensive to manufacture, and, in addition, many countries have strict restrictions on the production and turnover of radioactive materials.
Hydrogen cells can also be used as disposable batteries, but they cannot be used in smartphones. Hydrogen batteries are consumed quite quickly: although your gadget will last longer on one cartridge than on a single charge of a regular battery, they will have to be replaced periodically. However, this does not prevent the use of hydrogen batteries in electric vehicles and even external batteries: so far these are not mass devices, but no longer prototypes. And Apple, according to rumors, is already developing a system for refilling cartridges with hydrogen without replacing them for use in future iPhones.
The idea that a battery with a high specific capacity can be created on the basis of graphene was put forward back in 2012. And so, at the beginning of this year in Spain, it was announced that the construction by Graphenano of a plant for the production of graphene-polymer batteries for electric vehicles was announced. The new type of batteries is almost four times cheaper to manufacture than traditional lithium-polymer batteries, has a specific capacity of 600 Wh / kg, and it will be possible to charge such a 50 kWh battery in just 8 minutes. True, as we said at the very beginning, this will require a power of about 1 MW, so such an indicator is achievable only in theory. Exactly when the plant will start producing the first graphene-polymer batteries is not reported, but it is quite possible that Volkswagen will be among the buyers of its products. The concern has already announced plans to produce electric vehicles with a range of up to 700 kilometers from a single battery charge by 2018.
As for mobile devices, so far the use of graphene-polymer batteries in them is hampered by the large dimensions of such batteries. Let's hope that research in this area will continue, because graphene-polymer batteries are one of the most promising types of batteries that may appear in the coming years.
So why, despite all the optimism of scientists and the regularly appearing news about breakthroughs in the field of energy conservation, are we now seeing stagnation? First of all, the point is our high expectations, which are only fueled by journalists. We want to believe that a revolution in the world of batteries is about to take place, and we will get a battery with a charge in less than a minute, and with an almost unlimited lifespan, from which a modern smartphone with an eight-core processor will work for at least a week. But such breakthroughs, alas, do not happen. The introduction of any new technology into mass production is preceded by many years of scientific research, sample testing, the development of new materials and technological processes, and other work that takes a lot of time. After all, it took those same lithium-ion batteries about five years to go from engineering prototypes to finished devices that could be used in phones.
Therefore, we just have to be patient and not take the news about new food elements to heart. At least until there is news of their launch into mass production, when there is no doubt about the viability of the new technology.
We read the question trudnopisaka :
“It would be interesting to know about new battery technologies that are being prepared for serial production."
Well, of course, the criterion for mass production is somewhat stretchable, but let's try to find out what is promising now.
Here's what the chemists came up with:
Cell voltage in volts (vertical) and specific cathode capacity (mAh / g) of a new battery immediately after its manufacture (I), first discharge (II) and first charge (III) (illustration Hee Soo Kim et al./Nature Communications) ...
In terms of their energy potential, batteries based on a combination of magnesium and sulfur are able to bypass lithium batteries. But until now, no one could make these two substances work together in a battery cell. Now, with some reservations, a team of specialists in the United States has succeeded.
Scientists at the Toyota Research Institute in North America (TRI-NA) have tried to solve a major problem facing the development of magnesium-sulfur batteries (Mg / S).
Prepared based on materials from the Pacific Northwest National Laboratory.
The Germans invented the fluoride-ion battery
In addition to a whole army of electrochemical current sources, scientists have developed another option. Its declared advantages are lower fire hazard and ten times higher specific capacity than lithium-ion batteries.
Chemists at the Karlsruhe Institute of Technology (KIT) have proposed the concept of batteries based on metal fluorides and even tested several small laboratory samples.
In such batteries, fluorine anions are responsible for charge transfer between electrodes. The anode and cathode of the battery contain metals, which, depending on the direction of the current (charge or discharge), are converted in turn into fluorides or reduced back to metals.
“Because a single metal atom can accept or donate multiple electrons at once, this concept achieves extremely high energy densities — up to ten times that of conventional lithium-ion batteries,” says co-author Dr. Maximilian Fichtner.
To test the idea, German researchers created several samples of such batteries with a diameter of 7 millimeters and a thickness of 1 mm. The authors studied several materials for electrodes (copper and bismuth in combination with carbon, for example), and created an electrolyte based on lanthanum and barium.
However, such a solid electrolyte is only an intermediate step. This fluoride ion conductive compound only works well at high temperatures. Therefore, chemists are looking for a replacement for it - a liquid electrolyte that would act at room temperature.
(Details can be found in the institute's press release and in the Journal of Materials Chemistry article.)
Batteries of the futureIt is difficult to predict what the battery market will hold in the future. Lithium batteries are still at the forefront, and they have a lot of potential thanks to lithium polymer developments. The introduction of silver-zinc elements is a very long and expensive process, and its expediency is still a debatable issue. Fuel cell and nanotube technologies have been praised and described in the most beautiful words for many years, but when it comes to practice, the actual products are either too bulky or too expensive, or both. Only one thing is clear - in the coming years this industry will continue to actively develop, because the popularity of portable devices is growing by leaps and bounds.
In parallel with notebooks focused on autonomous operation, the direction of desktop laptops is developing, in which the battery rather plays the role of a backup UPS. Samsung recently released a similar laptop without a battery at all.
V NiCd-accumulators also have the possibility of electrolysis. To prevent explosive hydrogen from accumulating in them, batteries are equipped with microscopic valves.
At the famous institute MIT Recently, a unique technology for the production of lithium batteries was developed by the efforts of specially trained viruses.
Despite the fact that the fuel cell looks completely different from a traditional battery, it works according to the same principles.
Who else can suggest some promising directions?