How electric bike batteries work

An e-bike battery provides that extra power to your ride. Lithium-ion batteries for bikes - as well as electric bike motors - are essentially the components that set your e-bike apart from a regular bike. When you start to pedal, your battery and motor will kick in to give you a boost (up to 250 watts and a maximum speed of 15.5mph).

There are three basic measurements that impact an e-bike's performance and your ride: voltage, amps, and watts. The best way to think about these are:

  • Volts tell you the speed potential - the higher the voltage, the faster energy is pushed through the bike motor

  • Amps refer to the electrical current - so basically how much power there is in your bike

  • Watts is volts x amps. Think of this as a real measure of the bike's power.

It's also helpful to think about amp hours (aH), which is the capacity of your bike. The amp hours reading will let you know how much usable energy current will be delivered per hour. Similarly, watt-hours (wH) are the number of watts that can be expended in an hour.

Even if, like us, you're not necessarily an expert in physics, it's still really useful to understand the basics to make sure you're getting the right battery pack for your desired rides. Moreover, if you experience any battery issues, you'll be better prepared for how to fix them.

If you’re going to be cycling along challenging tracks where you will need a lot of power over long distances and steep hills, you need to know how your battery pack's voltage and amp hours can support you. So, if you’re going to be really pushing your bike for long distances and high speeds, you’ll probably want to go for a larger battery size.

Or let's say, you're a bit low on e-bike battery power and need your bike to eke out an extra mile, then you'll need to be able to manage your amps properly (i.e. use less power and slow down to make it home).

Whilst watt-hours can give you an idea of how much electric energy the motor can handle, it is ultimately up to your cycling style to get the best performance out of the e-bike. To figure out battery capacity and usable capacity, you'll want to look at both amp hours (aH) and watt-hours (wH).

What types of batteries do electric bikes use?

All Raleigh electric bikes use lithium-ion batteries. These (often referred to as Li-Ion batteries) are generally lighter batteries, which is also why they're often used in laptops and phones. Obviously, you don't want a huge battery weighing down your bike when you're out cycling. That's why e-bikes use an efficient lithium-ion battery pack to provide as much energy for as little weight as possible.

Lithium-ion batteries are also great at holding their charge and have long battery life. In fact, a lithium-ion battery pack only loses about 5% of its charge per month in comparison to a 20% loss for NiMH (Nickel-metal hybrid) and lead acid batteries.

This is because lithium batteries have little to no memory effect. This means that the lithium cells can handle hundreds of recharging cycles, even without a complete discharge of the battery between recharges. In other words, you don't have to worry too much about overcharging.

Centre and rear mounted batteries are more common across the Raleigh range, providing better performance and better handling. Rear-mounted batteries, such as on the Motus Tour low step, provide better handling and traction due to the added weight at the rear of the bike. It adds a smoother more natural feeling of acceleration, and we think it looks neater mounted to a rear rack.

DO ELECTRIC BIKE BATTERIES HAVE FUSES?

Sometimes e-bike batteries stop working as efficiently as they could. You may see a slip in power that comes without any apparent faults or when you know the battery is properly charged.

One possible reason for a drop in lithium battery performance could be the battery fuse failing. The battery fuse is a safety device that breaks electrical currents if they get unsafe. They also can only work once before affecting the battery performance.

If you find yourself wondering why you can't get the power you're used to, the first thing you should do is test your e-bike battery charger and the battery itself. You want to check that there are no faults and that the entire battery pack is properly holding charge. You may also want to use a battery monitoring system; if you do test your battery with a voltmeter or similar tool and it reads '0V', your fuse might be to blame.

If you're a bit uneasy about taking a battery pack apart, take it to your local specialist bike shop for assistance. But if you're feeling keen to do it yourself, you can find the fuse in the centre of the battery. If it's broken or has some burnt links, then there's a good chance the fuse might be the culprit and will need replacing.

It is rare for a bike fuse to go, but it is an easy fix if it does. As you get to know your e-bike and your riding style, you'll be more in tune with any issues that crop up.

How long do electric bike batteries last?

*Based on a rider weight of 12 stone, with an average speed of 10mph in 'tour' mode. Calculated using Bosch's eBike Range Assistant.

ModelAverage DistanceMotorBattery
Motus37 miles*Bosch Active LineBosch Power Pack 300Wh, 36V
Motus Tour51 miles*Bosch Active LineBosch Power Pack 400Wh, 36V
Motus Grand Tour63 miles*Bosch Active Line PlusBosch Power Pack 500Wh, 36V
Motus Kompact37 miles*Bosch Active LineBosch Power Pack 300Wh, 36V
Centros51 miles*Bosch Active Line PlusBosch Power Tube 400Wh, 36V
Centros Tour63 miles*Bosch Active Line PlusBosch Power Tube 500Wh, 36V
Centros Grand Tour63 miles*Bosch Active Line PlusBosch Power Tube 500Wh, 36V

How can I optimise the battery range of my electric bike?

There are a couple of tips and tricks that can aid the range that your bike will take you.

Cadence: Slow pedalling is costly in terms of energy, whereas keeping your cadence above 50 revolutions per minute can optimise your drive unit.

  • Weight: Less luggage will keep the total weight of the bike down and keep your e-bike running for longer.

  • Starting & braking: Just like with a car, it's more efficient on your battery and motor to keep cycling for a longer distance with a constant similar speed, rather than short bursts of sprint cycles.

  • Gear shifting: Keeping in the correct gear will ensure the bike is more efficient, some of our e-bikes do this automatically.

  • Tyre pressure: Always inflate tyres to the maximum permissible tyre pressure.

RALEIGH E-BIKE BATTERIES

Although all Raleigh electric bike batteries are lithium-ion, each range of bikes has a different motor system and therefore a range of different battery manufacturers. We currently have TransX, Bosch and Suntour battery systems.

All Raleigh e-bikes provide watt-hours (Wh) information so that you can choose the right e-bike for your rides. If you need a bike that can last long periods, search for bikes with higher watt-hours. If you're looking for speed for that morning commute or city riding, search for those bikes that mention voltage like the Centros or Pro Cargo Bike, which carry 36V batteries to give you that extra speed.

We've outlined each of the battery features below.

TranzX Battery

  • 260wh battery

  • Up to 50km range

  • Small, light and compact

Featured on: Stow-E-Way Folding e-bike

Close-up picture of a TransX Battery

Suntour Battery

  • 400wh battery

  • Up to 100km on a single charge depending on the level of assistance

  • Frame Mounted

Featured on: Array

array ebike battery

Bosch Battery

  • 300WH-500WH

  • Up to 220km in range on a single charge

  • PowerPack and Powertube

Featured on: Motus and Centros

array battery

Electric Bike Battery Positions

Frame-Battery

  • Used on our crossbar and new low step model

  • Up to 500WH

  • Easy removal and charging

  • Ergonomic design

Frame Integrated

  • Featured exclusively on the Centros

  • 500WH battery

  • Easy Removal and charging

  • Bosch Powertube

array battery close up

Electric bike batteries explained - FAQ

How long does an e-bike battery last?

As a general rule, a good electric bicycle battery typically lasts around 5 years on average. However, there are lots of factors that can affect e-bike battery life. These can include the type of battery, quality of manufacturer, wear and tear, amount of use, maintenance and storage. Learn more about common e-bike battery problems.

Where is the best place for the battery on an e-bike?

Batteries mounted at the rear of the bike or in the centre of the frame are the most common, and are featured across Raleigh’s electric bike range. Rear-mounted e-bike batteries generally offer smoother handling and a sense of acceleration, thanks to weight being anchored at the back of the bike.

How do I charge an electric bike battery?

When you receive your electric bike, you'll also receive a charger and a key. This key will allow you to unlock the battery from the bike and charge it indoors. The screen on your e-bike will inform you when your battery is low so you'll know the best time to charge your e-bike battery.

To charge the battery indoors, simply connect the charger and plug it in. Although the batteries are tested and safe, try not to keep your battery plugged in longer than it needs to be, in order to prolong its life.

Should I keep my e-bike battery fully charged?

Though e-bike batteries are durable, it's not recommended to keep them plugged in and charging after they've reached full battery capacity. If you're going to be keeping the bike battery in storage, it's generally recommended to keep it at around 30-60% capacity.

What is a good battery capacity for an e-bike?

There are lots of factors in choosing the right size and type for your e-bike electronics. For example, if you're going to be doing lots of uphill cycling or riding in particularly challenging conditions, you might want to invest in a larger-capacity battery. For normal usage (commuter cycling, leisure cycling etc), a standard e-bike battery - such as the 400Wh 60-mile model on the Raleigh Array - is likely to be more than enough.

Another factor to consider is weight - a more powerful battery will be heavier, so if you're looking for a lightweight e-bike (or a folding e-bike) you'll likely want to opt for a lighter battery. 

You also need to think about how much you’ll be loading up your bike with. Batteries drain faster under more strain, so if you’re planning on packing up your bike bag with a change of clothes, groceries or other items, you might want to opt for a more powerful battery.

What do Ah and Wh mean for e-bike batteries?

Amp-hours (Ah) and watt-hours (Wh) both refer to the capacity of a bike battery, though Wh is generally the more common measure. So, how is a bike's power calculated? Power is simply calculated by multiplying a bike's voltage by the current.

So, take the battery's capacity - so a 20Ah battery in theory supplies 1 current ampere for 20 hours (or 20 or an hour). Then multiply this by the battery's voltage - typically 36v, 24v or 48v - to get the watt-hours.

How do I maintain and care for my electric bike battery?

Taking care of your electric bike is relatively easy. Basic tips for keeping your electric battery cells healthy are to keep a light load on your bike to avoid overworking it. When it comes to storing your bike while you're not out cycling, storing it at a temperature of 0 to 20 Celsius is always recommended. Also, try to store it away at approximately 30 to 60% charge.

It's also best to park your e-bike in the shade as opposed to direct sunlight when you're out and about to protect the battery from overheating.

For more tips on keeping your electric bike in tip-top shape, check out our handy e-bike maintenance guide.

Are e-bike batteries waterproof?

In short, batteries on an electric bicycle are not waterproof, but they can handle the rain. Think of it as similar to your phone - it's not the end of the world if you get it a little wet in the rain for a bit, but you wouldn't want to be dunking it in puddles.

To make sure your e-bike battery doesn't get waterlogged and damaged, make sure to fully dry it after a particularly wet day (inevitable in this part of the world).

Can I repair an e-bike battery?

Certain e-bike battery elements can be repaired, like its fuses or a few battery cells which can be replaced. Through regular maintenance and inspection, you can not only extend the battery life but also catch any issues before they really affect your ride.

Of course, sometimes the battery can be beyond repair either because of the damage or simply its age (circle of life, we're afraid). In those cases, it might be best to start shopping around for your next electric bike.

Can electric bike batteries be replaced?

It's highly unlikely you'll ever need to replace your electric bike battery over the lifetime of your bike, due to the technology's durability. While it is often possible to replace the batteries and electric motors on e-bikes, it's more often than not cheaper and easier to look at investing in a new bicycle altogether. When your e-bike battery begins to cause you trouble, it's likely going to be time for an upgrade!

Batteries are expensive on their own and you're best to buy yourself a new bike. If you are concerned about any battery or e-bike issues, be sure to register the warranty of your bike online.

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