The battery is a key component of any electric bike. If you look after it, you shouldn’t need to replace it for 4-6 years. We’re going to show you how to care for your e-bike battery to maximize its performance and reliability.
Your new ebike battery uses Lithium Ion chemistry in the form of 18650 cells which look like oversized AA batteries. (If you're curious, each cell is 18mm in diameter and 65mm long, hence the name.) Many of these cells are assembled into a battery to produce 36 or 48 volts and a specific capacity, depending on the bicycle it is made for. The overall shape and physical dimensions of the battery dictate how it is assembled and often also how much capacity it can hold.
What’s the difference between ebike lithium batteries and normal batteries?
Lithium-Ion batteries require different handling from other types of batteries. They don't exhibit the 'memory' effect seen on nickel-based batteries and offer a much wider usable charge range than lead batteries. Inside the battery case is a battery management system (BMS), which is an onboard computer that controls how/when power flows in or out of the battery.
The BMS protects the cells from overcharging and over-discharging but also balances the cells so they match as close to each other as possible, which will make the battery perform better and improve your electric bike's performance. When charging, your battery will charge to 80+ percent of charge in a relatively short time - the rest of the time is what we call the 'satiation' portion of the charge cycle, where each individual cell is fully charged and balanced. It's ok to skip the satiation charge occasionally if you're in a hurry, but it is important to do it regularly.
How long do ebike batteries last
YOUR EBIKE BATTERY SHOULD LAST 3 YEARS AT PEAK PERFORMANCE AND THEN SLOWLY DECLINE.
It’s true that a lithium battery has a finite number of charge cycles and that’s how the lifespan of the battery is calculated, however, it’s not quite a straightforward situation in real life.
A full charge cycle is from 0 to 100%, which is rare for most riders since few people deplete their battery all the way. This also means that when they charge their battery, they are only charging part of a full cycle.
If you ride your battery down to 45%, come home and charge it back up, you have only charged 0.55 of a charge cycle and not 1 full charge as most people are afraid of.
Charge cycles are an important metric for any battery, but for most users, they simply won't even get close to wearing out a battery by using it. Time takes its toll on us all, and batteries are no exception. Even if you do everything right with your battery, it will eventually degrade due to time.
How to get the most out of your ebike battery
It’s recommended that you use the battery as frequently as possible. The health of your battery is more contingent on frequent use than it is on how you deplete it. Ride your bike as often as you can and charge it when you're done.
You will also reduce the risk of being stranded due to battery issues if you keep it charged up all the time. The last half of the battery charge depletes faster than the first half, plus your motor produces more power when the battery is closer to full charge.
The bottom line is ride often and charge often. It’s better to deplete and charge in small stages than to regularly drain the battery down to 0.
Smart Charging Your Bike’s Battery
Your new ebike also came with a smart charger for the battery. We use standard 2 amp chargers because charging faster than that will generally shorten the lifespan of the battery.
The charger detects when a viable battery is plugged in and then charges until it sees the battery has reached full. Once the battery is full, the charger turns off and indicates such by switching the light from red to green.
The term smart charger is to indicate that the charger automatically senses when a battery is plugged in and automatically stops charging. This does not mean you can leave a charger plugged into the battery long term. The charger will attempt to search for a battery periodically and this pulse of power into the battery will hurt it over time.
You can easily leave the charger plugged into the battery for a day or two (ideally for as short a period as possible, but not for long term.
Don’t worry about the charger finishing charging at midnight and leaving it until morning. That is no big deal. Worry about plugging it in on Friday and unplugging it on Monday!
You should certainly never plug the charger in at the end of the riding season and then unplug it in the spring when you ride again.
Things to Consider with a brand new battery:
- The battery is mostly charged, but due to it having sat for some time, will not exhibit full potential until 4-6 charge cycles.
- Doing an initial charge will help wake up the battery and also balance the cells. This will provide a good/solid start to a healthy battery.
- You can test ride a bicycle before doing the first charge. But don’t go on a long ride until you have at least finished the conditioning charge.
- You don’t need to take it easy on the battery the first time riding.
- Avoid 35+ mile rides until you have at least 4 charge cycles on the battery.
THE FOLLOWING TIPS HELP IN MAINTAINING EBIKE BATTERY HEALTH:
- Partially deplete the battery regularly. Ideally at least once a week and not completely.
- Charge the battery regularly. Best is after every ride unless you are still over 90% charge.
- Unplug the charger from the battery as quickly as you can after its done charging. Hours are ok, days/weeks are not. Consider an inline timer if this is a concern for you.
How to Store your Electric Bike Battery
Keep batteries out of extreme cold and heat. Using them in cold or hot weather is not an issue, but storing them in a place that is not climate controlled could damage the battery. Lithium-Ion batteries are the happiest, in use, at the same temperature as a human body. For storage, a cool place is slightly better for the battery, but it is important that they stay above freezing.
If you need to store a battery long term, you will want to charge it every 30 days. Ideally, you want to discharge it partially, and then charge it again to 100%
The biggest reason for premature battery failure is lack of use.
Periods of non-use that exceed 3 weeks can cause a battery to go into “hibernation”. To get out of battery hibernation you need to charge and then use the battery for a few cycles. During this time you’ll experience a lower range and a bit less power. The battery should return to full performance once you do this a few times.