There are a lot of complaints about CityCoco-type electric scooters about the range, which is sometimes significantly lower than stated.
We're not talking about the e-bikes we sell.
We decided to write this blog with the hope of reducing the likelihood of an unsuccessful purchase of the CityCoco electric bike. To do this, we will tell you how not to buy a CityCoco electric scooter with bad spare parts, we will help you diagnose the cause of the problem and fix it if you come across such a device.
The lithium-ion battery is the biggest source of problems and is also the most expensive part of the CityCoco electric scooter. The engine ranks second in terms of cost and impact on range. We have written about engine problems in a separate article.
Complaints from owners of CityCoco electric scooters with low-quality batteries mainly boil down to the following:
— I have a 60V 12Ah battery, but the scooter drives a maximum of 10 km at an average speed.
— When riding uphill, the electric scooter turns off even when there is still a charge in the battery.
— Over the course of the year, the battery capacity is getting smaller and smaller, now it is not enough even to get under way.
How much should an electric scooter travel on wide wheels such as SEEV, CityCoco, Woqu and their analogues? Have any measurements been carried out or are all the figures an invention of the manufacturers?
The best way to check the range of an electric scooter is to cover a certain distance at a certain speed until it turns off completely. We used this technique in 2017. A man weighing about 70 kg (average weight) got on an electric bike and drove along the highway at maximum speed until it turned off. The conditions were chosen as ideal - dry flat road, heavily inflated tires and calm weather. The results are pretty decent. For example, the CityCoco Caigees 1200W electric scooter with a 60V 10 Ah battery covered 37 km, the CityCoco Ride electric bike with a 60V 20Ah battery traveled about 70 km, while the average speed was 35 km/h.
But in real life there are a number of factors that can affect the mileage:
- strong wind
- wet road
- climbing uphill
- heavy weight of the driver or the second passenger
- low air temperature
Almost every of our customers asks questions regarding the mileage of the CityCoco electric scooter, for example: "How much will I travel if I go at maximum speed?", "How long will I travel with the second passenger at a speed of 10/20/30/40 km/h?"
It will take a very long time to conduct an experiment that gives answers to these questions with each model of CityCoco electric bike in the traditional way, especially at low speeds, so we decided to change the testing methodology. To determine the mileage, we measured the instantaneous and average energy consumption of the electric scooter with a watt meter under various operating conditions.
The test was carried out on roads with descents, ascents and after rain. The tire pressure was reduced to 1.2-1.5 atmospheres. Measurements were taken with one passenger weighing 70 kg and two passengers weighing 140 kg to track the effect of increased weight on the range. The electric bike, at a speed strictly fixed using the cruise control, moved in one direction for about a kilometer. On CityCoco models, where there was no cruise control, they tried to keep the speed of 10 km/h manually. The rest of the electric scooters were tested at speeds obtained when driving in modes 1, 2, 3 of the electronic gear selector on the accelerator handle. During the test, the instantaneous energy consumption of the electric bike was read every second and then the average value for the distance traveled was displayed. This was followed by a movement in the opposite direction with similar calculations, and at the end the average value was determined for the entire path in both directions. This measurement made it possible to obtain a more accurate result, taking into account the influence of wind and unevenness of the road.
The results of energy consumption, as well as a decrease in mileage due to an increase in the weight of passengers from 70 to 140 kg, can be seen in table №1:
Table 2 contains calculations showing how much and on what battery these electric scooters will pass under the following test conditions:
The mileage values are marked in red, which in real life may be less due to a significant excess of the nominal battery current.
If you have tested your CityCoco electric scooter for the duration of a straight road run at a certain speed, and the results are significantly lower, then most likely you do not have the declared capacity in the battery or the engine on your electric scooter has a low efficiency. In real conditions, when tested on a dry and flat road in calm weather, the mileage is even higher than in the table.
Why is it that some users are fine, and the mileage is as promised, while others have so many problems?
The main reason may be that the battery capacity does not match the declared one. CityCoco e-bike batteries use 18650 cells. By following this link you can see how much the declared capacity of a 18650 battery can differ depending on the manufacturer. You are told a certain battery capacity, but in reality it is much less.
You can often hear the following question: "Why does my electric scooter pass the declared mileage at low speed with a quiet ride, but as soon as you start to actively accelerate or ride in a mountainous area, the mileage immediately drops several times?"
A lithium-ion battery will deliver less than the rated capacity as the discharge current increases. Let's take as an example the discharge graph of a Panasonic NCR18650B lithium-ion cell.
The battery is discharged with a current of 0.2C, 0.5C, 1C and 2C, where C is the nominal discharge current (for example, a 3300 mah battery has a nominal discharge current of 3300 ma). The area marked with a red circle with a cut-off threshold voltage of 3.0V on the discharge line with a current of 2C records the instant of complete discharge. It turns out that when the battery is discharged with a current of 2C (6.4 amperes), the battery will give out only 2.3 Ah, instead of the nominal 3.2 Ah. In cheap cells of unknown origin, the dependence of the given capacity on the discharge current is much greater.
Also at this link you can see how the battery capacity drops depending on the temperature.
With a quiet ride, the power consumption of your electric scooter is small, but with an active, fast ride, it sometimes doubles to three times. Active driving with a heavy load on the engine leads to a significant increase in current consumption, which can lead to a decrease in the capacity provided by the battery. This depends very much on the cells used in the battery. If the mileage decreases several times, or the electric scooter turns off altogether when driving downhill, then the battery has low quality cells or is unbalanced (have different voltages). In this case, the batteries operate under heavy load and, in addition to inconsistency with the declared characteristics, they will also have a shorter service life
It may be normal if battery switch off under load only when the ambient temperature is below 10 degrees, (in cold conditions, the battery capacity is temporarily reduced) and if the charge level is below 40%, and only if your peak engine power is several times higher than the rated capacity battery.
From our experience in disassembling and repairing cheap Chinese batteries, we can note that in most cases the cells themselves are of quite normal quality. But the battery is not only the elements themselves and their connection, but also the control board (BMS). In branded batteries, before assembling the battery, all cells are charged to the same voltage. In order for this condition to be met during the operation of the battery, the BMS has a balancing function (equalizing the voltage on all cells). In this case, the battery works stably and for a long time. Often in Chinese batteries, the cells are not voltage-equalized before assembling the battery. They have such a big difference in charge that under normal operating conditions even a balancing circuit (which is not present in every no name battery) does not help. As a result, if even one of the cells is discharged, the BMS simply disconnects the battery, and it turns out that its actual working capacity is significantly reduced. In addition, such a battery dies rather quickly, its service life is usually no more than a year.
If you do not ignore the symptoms of an unbalanced battery, equalize the voltage on its cells and, in addition, put a balancing board (if it is not there), then the same battery will leave much longer.
The balancing mode is activated only when the battery is fully charged, so it is very important to try to periodically charge the battery until it is fully charged and leave it connected for another couple of hours. If you never fully recharge the battery, the balancing board will not play any role, and a large difference in voltage and working capacity can occur on the cells. The voltage equalization process is carried out with a small current (up to 100 mA), therefore, a strong difference in charge with a standard balancing board cannot be completely equalized, and the battery life will be reduced. An uncalibrated charger that produces less than the required voltage can also cause premature battery wear, since in this case it will not be fully charged. Check that the voltage at the end of charging is 67.3-67.7V (if the battery has a declared voltage of 60V). If the voltage is higher than 67.8V and the charger does not reduce the current, the BMS board may go into emergency mode and the balancing process will not start. In about half of the cases, battery problems arise precisely from a poor-quality charger.
What batteries do we use? Do they have real capacity and other characteristics?
Our store specializes exclusively in the sale of CityCoco electric scooters, and to a lesser extent their counterparts, therefore we have extensive experience working with many factories in China. We dealt with several different brands of batteries, but when carrying out tests to measure their real capacity, we had to stop at only one version, which, when tested for high current discharge, corresponded to the declared characteristics (Hao Yang brand). The declared capacity of one cell is 2.5 Ah, and the actual one is 2.5-2.7 Ah. Since 2020, we also have cells with a capacity of 3 Ah. We don’t day that this brand is the best of the Chinese, but we believe that this is good choise. Batteries with cells from Samsung, Panasonic, LG cost at least one and a half times more, while they do not have any special advantages when used in electric scooters, except for a slightly increased cell capacity at the same size. The experience of using CityCoco electric scooters with Hao Yang batteries at the rental, where they work quietly for 3 years in daily operation, showed that the number of charge-discharge cycles also corresponds to the manufacturer's declared. The biggest role is played by the build quality of the battery itself and the balancing board.
There are many ardent fans of other types of batteries in the world, for example NMC, LiFePO4, LiNiMnCoO2. They will tell you whatever they want to throw mud at the Li-Ion type. Elements with such chemistry are more expensive for the same capacity and size. Does the battery life really depend on its chemistry? Why, then, the largest automaker TESLA, which has electric vehicles with the largest range and the longest service life (only an official guarantee of 8 years), uses chemistry in Li-ion batteries and, in most cases, 18650 or 26650 cells?
How to avoid buying an e-scooter with a poor quality battery?
In addition to lithium-ion batteries, CityCoco can also use lead-acid, lithium polymer.
Lead acid (Lead Acid) batteries are sometimes found in the cheapest versions of CityCoco, with a capacity less than 12 Ah. They have the lowest specific energy density, so a larger battery simply won't fit into an electric scooter sump. In addition, due to the use of lead, the total weight of such an electric scooter can reach 100kg, versus 60kg with other types of batteries. This is the cheapest type of battery and is installed in CityCoco for the purpose of economy, but it is so insignificant in relation to the total cost that it does not justify a number of disadvantages of using lead-acid batteries in this case
Lithium-polymer (Li-pol, Li-polymer, LIP, Li-poly) batteries are installed in analogs of CityCoco electric bikes - brands SEEV, ZERO. In their properties, they resemble lithium-ion. In practice, SEEVs life very little, despite the fact that they are manufactured by Samsung. In the rental, such batteries work out for only one season, in the second year they either significantly lose their capacity or swell, which is explosive. They consist of plates like batteries in a mobile. phones, and may grow in thickness. This is a significant disadvantage compared to 18650 lithium-ion cells, which can leak at most, which does not pose such a hazard.
A possible reason for premature battery failure and swelling in SEEVs lies in their small capacity. 12Ah is not enough for the 30A peak current, which becomes nominal with our driving style. The owner of this electric scooter is faced with another problem - the battery is thin (5 cm), and therefore a lithium-ion analogue (7 cm) will not fit in instead. One gets the impression that this manufacturer specifically uses such a battery for additional income. In Ukraine, such a new 12 Ah battery costs about $ 500, and for this price you can buy a 30 Ah lithium-ion battery, or 2 pcs 12 Ah.
In Zero electric scooters, the standard lithium-polymer battery, although with a larger capacity (20Ah), is fragile, and it is afraid of water, while, if it gets into the battery, it cannot be repaired. But the owners of Zero are more fortunate than the owners of SEEV electric scooters, because a lithium-ion analogue is standardly inserted into the box of this scooter.
First of all, before buying a CityCoco electric bike, check the type of battery installed. Based on our own experience, we recommend electric scooters with lithium-ion batteries. In case of any problem, they can be easily repaired and 18650 cells can be purchased easily. Lithium polymer and lead acid batteries are virtually irreparable, even with minimal problems.
Some cheap Chinese batteries can work more or less adequately for half a year, and then surprises are possible due to the lack of a balancing board, or poor welding of the elements that make up the battery. Therefore, be sure to pay attention to the warranty conditions. Quality batteries are guaranteed at least 12 months.
The battery must have spec stickers, a barcode, the manufacturer's website for that battery, an iridescent hologram (which is quite difficult to counterfeit), and a brand logo.
Batteries, on which paper is simply pasted, such as A4 with hieroglyphs, are suspicious. This is a so called “no name” battery of unknown origin. There are cases when, when disassembling such a battery, it turns out that the cells were released several years earlier than the assembly date indicated on the packaging.
Examples of suspicious "no name" batteries:
Examples of batteries we use (Hao Yang brand)
1) In a PCB or plastic case:
2) The option in a plastic or iron case can sometimes be damaged by impact, which will allow water to penetrate into the battery, therefore, in the fall of 2019, we began to use a battery in an iron case, (when choosing a capacity of 20 Ah) which is almost impossible to damage. Also, if you are afraid of a battery fire (although this does not happen with ours), then the iron case will not allow this to happen:
Attention! On the website of the manufacturer Hao Yang, you can find batteries that are the same in size and appearance, but with different capacities. A year after this article was written, Hao Yang brand batteries have become quite common in CityCoco electric scooters from other sellers, but unfortunately, their capacity does not always correspond to the declared one. This is despite the fact that the batteries have a factory hologram and a sticker with the characteristics of the battery and the capacity indicated on it. Considering the number of requests from non-our customers to check the battery capacity of HaoYang, which most often turns out to be 25% less than the declared one, it becomes obvious that the scooter is equipped with a cheaper battery, on which a sticker with its characteristics was changed, which, unlike a hologram, is very easy to counterfeit.
Therefore, if you have already bought an electric scooter, or are not going to buy from us, immediately check its power reserve in a straight line, so that you still have the opportunity to return it to the seller if there is a clear run with the declared characteristics.
We can check the capacity of your battery using a device specially designed by us for this purpose and draw a conclusion from our service center. The cost of the service is negotiated individually and depends on the battery capacity and the timing of the work.
Also, if necessary, we do all types of repair work related to restoring the capacity of your battery, balancing elements, etc.
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