Lifespan of an electric scooter battery: cycles, wear, and signs of degradation
A scooter battery doesn't simply die; it degrades over time, cycle after cycle and year after year. Its capacity decreases, its internal resistance increases, and the scooter loses range and power. The rate of this degradation depends heavily on how it's charged, stored, and used. Therefore, there is no single lifespan; rather, there are habits that shorten it, and others that extend it.
The essentials
- One cycle corresponds to the equivalent of a full charge, even if it is distributed across multiple partial charges.
- The number of charge cycles for a battery is measured in the laboratory, often up to 80% of its original capacity. This is a benchmark for comparison, not a guarantee.
- What causes the most wear and tear: heat, high currents, prolonged periods of being fully charged or completely discharged, and charging in cold temperatures.
- Signs of battery degradation: reduced range, sudden power cuts during acceleration, and voltage imbalances between individual battery cells.
- Swelling, unusual odors, or excessive heat: these are no longer signs of normal wear and tear; they indicate a potential hazard.
What "cycle" means
A cycle refers to the equivalent of a complete discharge and recharge. Two half-discharges, each followed by a recharge, also count as one cycle. Cell manufacturers specify a number of cycles until the capacity decreases to a certain percentage of its initial value, often 80%.
This figure depends heavily on the test conditions: charging current, discharging current, depth of discharge, and temperature. A power cell tested at a high current will show fewer cycles than a power cell tested gently, but this doesn't necessarily mean it's "worse." Our guide on reading the specifications of a lithium cell explains how to interpret this data.
In addition to cycle-based degradation, there is also "calendar aging": a battery also deteriorates while at rest, and this process is accelerated if the battery is stored fully charged and in a warm environment.
What causes battery wear
Heat
This is the main culprit. A battery that gets very hot during each ride, whether it's charged while still warm or left in the sun, will age more quickly. Allowing the battery to cool down before recharging is a simple and effective practice.
Strong currents
Constantly discharging the cells close to their limit, run after run, causes them to heat up and accelerates their wear. This is especially true when a controller has been upgraded to provide more power on an original battery. A battery sized for the required current will operate more comfortably: this is the purpose of Performance batteries.
Extreme load conditions
Leaving a battery at 100% charge for weeks, or even worse, completely discharged, puts stress on the cells. A battery left completely discharged can, through self-discharge and the consumption of the Battery Management System (BMS), reach a voltage level where it can no longer be safely recharged.
Charging in cold weather
Charging a lithium-ion cell below 0°C can cause metallic lithium to deposit on the negative electrode. This deposition is irreversible: it reduces the cell's capacity and can make it more susceptible to failure. It is always recommended to charge a battery that has returned to room temperature.
Imbalance
If a group of cells drifts relative to the others, it will be the first to reach the high and low voltage thresholds, and it will work harder than the others. The BMS and its balancing system correct these discrepancies, provided that the battery is fully charged from time to time.
Signs of a worn-out battery:
| What you are observing | What this indicates |
|---|---|
| Gradual decrease in battery life over several seasons | Normal capacity degradation |
| Sudden power cuts during acceleration that weren't present before | Increased internal resistance, or a weaker group of cells |
| The voltage drops quickly after charging | Group of cells that are worn out or imbalanced |
| The battery is getting hotter than it used to, even with the same usage | Increased internal resistance: Requires inspection |
| Swelling, odor, leakage, overheating at rest | Warning: Do not charge or use |
A swollen battery is covered in a separate guide: swollen battery, what to do immediately.
Extending the lifespan of your battery
- Allow the battery to cool down before charging it, and charge it at room temperature.
- For everyday use, avoid leaving the battery fully charged or completely empty for extended periods. To maintain optimal battery health, perform a full charge occasionally.
- For extended storage, it's best to store the battery at a partially charged level, in a cool and dry place.
- Do not demand more current from the battery than it is designed to provide.
- Use the charger specifically designed for the battery.
These steps are detailed in our guide for charging your electric scooter battery: best practices.
Workshop tip
A battery with a connected BMS (Battery Management System) is like a health record: it displays the voltage of each cell group and the number of charge cycles. Get into the habit of checking the voltage differences between the groups after a full charge: this is the best early indicator of a cell that is starting to degrade. All of our scooter batteries are assembled in our workshop using branded cells and come with a 2-year warranty. For a diagnosis of your current battery, contact our workshop.
Frequently Asked Questions
How many kilometers can you travel on a scooter battery?
There's no single, reliable number: everything depends on the battery cells, the heat generated, the current draw, and charging habits. A battery that is treated gently can last much longer than one that is constantly pushed to its limits.
Should you avoid charging the battery to 100%?
For regular use, it's best to stop charging a little before the battery is fully charged, and avoid leaving it at full charge for extended periods, as this can shorten its lifespan. However, a passively balanced Battery Management System (BMS) requires regular full charges to properly balance the individual cells.
Can only the worn-out cells be replaced?
It's a delicate process: a new cell placed among worn cells will quickly become unbalanced. Depending on the condition of the battery pack, you either replace a complete group of cells or the entire battery. This is a job for a specialist.
Does a battery that isn't being used still degrade?
Yes, it degrades more slowly. Calendar aging is faster if the battery is stored fully charged or in a warm environment. A battery that is left completely discharged can also become irreparable.