To keep your high-end electric bike in top condition, you need to know how to test its battery. Just like smartphones and laptops, the state of your e-bike’s battery can significantly impact its performance.
The battery contributes to the performance of a better electric bike. But unfortunately, it is also the most expensive component and requires the most maintenance to maximize its life and performance.
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With this in mind, it is essential to know that even the batteries in an electric mountain bike can show slight signs of weakness, but that does not mean they need to be changed. In this case, you should perform a battery test. Find out how to do it.
Why test electric bike battery?
For example, a battery test is performed when you detect warning signs of weakness while riding an electric cargo bike. In particular, if the battery has been charged to 100% and in a short period, a significant drop in charge level is noticed. The test becomes essential if this problem recurs.
But sometimes, the battery problem can be insidious. For example, you may feel a lack of power from the electric bicycle, even though your pedaling pace provides a high level of assistance.
Otherwise, the failure may come suddenly, interrupting the electric assist for no apparent reason. Regardless of the nature of the problem, when one of these scenarios occurs, it is appropriate to test the bike’s battery to repair it.
At the same time, this test is helpful for people considering putting their electric mountain bikes back on the market. Indeed, a certificate attesting to the battery’s excellent quality helps justify the bike’s sale price.
Read also: What to think of a second-hand e-bike? And, What is e-bike resale value?
Testing the electric bike battery with a multimeter
A multimeter is a small, portable device for measuring a battery’s current, resistance, and voltage. It has a small display showing each result. There are two types of multimeters, analog and digital. In general, digital multimeters provide more reliable data.
A multimeter makes it easy to test an electric fat bike battery; follow these steps.
Connecting the multimeter
Before starting the test, the battery of the electric bike must be fully charged. This process can take up to 8 hours. In addition, if the battery is not removable, it is necessary to check that it has been adequately attached to the bike frame.
Then, insert the tips of the multimeter into the port of the adapter or the connector. Be careful, however, not to force them or apply firm pressure, as this could damage either unit.
Testing battery capacity
In general, multimeters have two functions: one for AC and DC and the other for testing the battery’s charge. Therefore, you should set your multimeter to DC mode. As a general rule, the AC function should not be used for a folding electric bicycle, as it may cause the battery to overcharge.
This test determines whether the battery is capable of operating the electric bicycle. Or if its energy capacity is sufficient to ensure communication with the motors and other applications.
To test the battery voltage, switch the multimeter to volts mode. Refer to the manual for the voltage range of your e-bike brand. If the battery has been charged for hours, its voltage should match the value in the manual.
If the voltage drops below the specified level, the electric bicycle will stop working to prevent damage to the unit. In this case, you will receive a message inviting you to recharge it. On the other hand, if the voltage is too low, about 10 volts, but the bike still works, the monitoring system needs to be repaired.
Check the current
Now we need to check the current. The current is the maximum charge and energy the electric bicycle battery can hold. It also represents the amount of power discharged in one hour.
This test allows us to evaluate the longevity of the battery. To do this, you need to compare the value indicated by the meter with the one in the manual. If you find that you need more power during your rides, the battery may be over-discharged.
Read also: How much elevation / altitude can electric bikes climb? And, Can electric bikes go up steep hills?
Another approach to ensuring the longevity of your electric bike is to test the resistance of the battery. Resistance is the amount of restriction in a battery that directly impacts current. It should be the last parameter on your meter. If your resistance is high, this may be the reason for overheating problems.
Battery management system
In addition, there are electric bike models, many of which have an integrated battery management system. That is also called a control console. This system allows you to have all the data on the level of the battery via a screen. This one also allows displaying the speed, the time, or the assistance mode.
It is beneficial for analyzing the current and voltage and protecting the battery cells from temperature variations or the effects of charging/discharging. This management system monitors the battery’s condition and extends its life.
The only drawback to this tool is that it is significant and may take up some extra space on the handlebars. Generally, multimeters have more features compared to an average battery management system.
Battery test: call in a professional
It is possible to test the battery of an electric bicycle yourself. However, you should know that the result obtained will be questionable. For those who still want to try, you must charge the battery.
Then, it is necessary to calculate the duration required for a complete load. To do this, you need to know the charger’s speed and the battery’s performance. At the end of the charging process, if the power delivered by the battery is lower than expected, the battery starts to weaken.
Read also: What is the difference between e-bike batteries? And, How far can e-bikes go? What is the e-bike range?
However, controlling the initial parameters and calculating the actual deviations is sometimes hazardous. For this reason, it is better to trust a professional for increased safety. The latter will be equipped with a high-performance measuring tool that will make it possible to determine easily and quickly what is going on. On average, the test costs a maximum of 40 or 50 dollars or euros.
At the end of the test, the professional will produce a detailed diagnosis that will indicate if it is necessary to replace only some aspects of the battery or to replace it entirely.