E-bike battery position

To choose the right e-bike, we advise you to test the bike properly. Take a test ride or, better still, take the bike home for a few days to get a real feel for it. Once you have tried several bikes, you have a clear picture of what to expect from each e-bike.

In the integrated version the battery is usually fitted in the down tube, but these days you also find batteries in the top tube or the seat tube of the frame, either fixed or removable. With the battery tucked away in the frame, an e-bike looks almost like a normal bike.

E-bikes that have this type of battery: e-mountain bikes, e-trekking bikes, e-city bikes, e-road bikes and e-cargo bikes.

Advantages:

• Looks good
• The battery is built in aerodynamically
• Rides like a normal bike
• Enough room for a bottle cage
• Wiring harness hidden in the frame
• Close to the mid-drive motor
• Low centre of gravity
• Sturdy construction

Disadvantages:

• In some cases the integrated battery is a little heavier
• Sometimes the battery cannot be removed, or only with difficulty
• The whole e-bike has to be taken to a socket
• Often a more expensive construction
• The newer integrated e-bike batteries are often difficult to re-cell

You see rack batteries a lot on city bikes and on bikes that were converted to electric later. They are easy to take out and quick to swap. The drive you find most often with this setup is a front-wheel motor, although in recent years more and more rear-wheel and mid-drive motors have come onto the market.

E-bikes that have this type of battery: e-city bikes and bikes that were converted to electric.

Advantages:

• Ideal for step-through bikes
• Unobtrusive, depending on the design
• Fits almost any bike
• The battery can almost always be removed
• Almost all rack batteries can be re-celled

Disadvantages:

• Long wiring harness, so more chance of faults in the cables
• Centre of gravity moves up and to the rear
• Handles a little differently from a normal bike
• Fitting a child seat can be awkward

On some e-bikes the battery sits in front of or behind the seat tube. This position under the saddle is common on Flyer bikes and folding bikes, for example. The design is often chosen for very compact e-bike models that are mainly meant for city traffic.

E-bikes that have this type of battery: e-city bikes, e-cargo bikes and electric folding bikes.

Advantages:

• More room at the front of the frame triangle
• Better weight distribution
• Often no long cables needed
• Rear rack stays easy to get at
• A higher capacity is often possible
• The battery is easy to replace
• Easy to reach
• The battery can be re-celled in most cases

Disadvantages:

• Unusual design
• Stability depends heavily on the design
• Sometimes costs more because of the development work
• Not a standard bike

The position of the battery has a marked effect on the centre of gravity and the handling of an e-bike. A battery integrated into the frame gives a lower centre of gravity, so the bike rides more like a normal bike. A battery under the rear rack moves the centre of gravity up and to the rear, which changes the handling and can make the bike less stable.

Batteries integrated into the frame give a cleaner, more aerodynamic design, so the e-bike looks more like a traditional bike. Batteries under the rear rack or by the seat tube have more influence on the design of the bike, and sometimes make it look unusual.

The advantages of an integrated battery are its looks, the aerodynamic way it is built in, a lower centre of gravity and the space it saves. The disadvantages are that the battery is sometimes difficult or impossible to remove, so the whole bike has to go to a socket for charging, and that this construction is often more expensive.

Yes. Batteries under the rear rack are generally easy to remove and replace. They are often simpler to re-cell than integrated batteries as well.

Batteries by the seat tube give a better weight distribution and are often easier to get at for replacement and cell replacement. This position often allows a higher capacity and needs shorter cables, which makes the bike more stable and more efficient.

Batteries integrated into the frame are often harder to re-cell than external batteries, because of how they are built and how they are fitted into the frame. Many of them can still be re-celled. The exceptions are batteries where resin has been used to seal everything off, batteries that are locked by software and some newer types such as the Bosch PowerTube. See which batteries we cannot re-cell.

With an integrated battery you often have to bring the whole bike to a socket, whereas an external battery can be taken off and charged on its own. That matters if you have no socket within easy reach of where you keep your bike.

Think about handling, looks, how easy the battery is to reach for charging and maintenance, and whether it works with your accessories. Try out different e-bikes to find out which battery position suits the way you ride and what you need.