How to find the right e-bike battery: 5 steps

Step 1: First check whether you really need a new battery

Many people go straight to looking for a new battery. In practice it often turns out that:

Only the fuse is faulty
Only the electronics (BMS/circuit board) are faulty
The capacity has dropped (a cell replacement, or re-celling, is possible)

That is why we at KWS Seuren always advise:

First have your battery inspected to see whether it needs replacing.

Have your battery inspected

Step 2: Read the label on your battery

Every battery has a sticker with the key information.

You will usually see:

Brand name (e.g. BionX, Yamaha, QWIC, Cleantron, Flyer)
Voltage (e.g. 36V)
Capacity (Ah)
Energy (Wh)
Sometimes a model number or article code

Examples of what you may come across:

36V / 10Ah / 360Wh
36V / 13.8Ah / 497Wh
36V / 20Ah / 750Wh

These are important clues, but they don't tell the whole story.

Step 3: Voltage matters, but it is not enough

Many customers think:

"My battery is 36V, so any 36V battery will fit."

That is not true.

Many e-bikes have a 36V system, but the batteries can still differ in:

Electronics (BMS)
Connector and pin configuration
Software communication
Casing and mounting

Even two batteries that are both 36V and 500Wh may not be interchangeable.

Step 4: Look at the system, not only the bike brand

A common mistake:

"I have a Gazelle, so I need a Gazelle battery."

But one brand can use several systems.

Gazelle, for example:

Innergy
Shimano Steps
Panasonic
Bosch
Yamaha

Three Gazelle bikes with a rear rack battery can need completely different batteries.

So it is important to look at:

What does the label say?
Which system does the display show?
What does the connector look like?

Step 5: Search the webshop by brand and compare the battery

This is how you usually find the right battery in our webshop: search by brand first (for example Gazelle, Sparta, QWIC, Flyer, Yamaha). The brand is often on the battery label, and usually on the bike or the display too. Go to the brand page under E-bike batteries, choose your brand and look through the batteries listed there.

Then choose the battery that looks most like your own (shape, rear rack or frame, handle/lock). The product page gives extra details such as voltage (V), capacity (Ah/Wh), type of mounting and connector (e.g. 5 pins), so you can check that it matches.

Search by brand

I see "Cleantron" (36V / 387Wh)

This is a battery that is often used on Van Raam bikes. In this case you can search by the brand of the bike and then check whether the product page shows the same features as your battery.

I see 36V and Flyer

You also see 750Wh, which tells you this is a sizeable capacity. Search for Flyer and look for the right 36V battery: check whether it has a light, what the charging connector looks like and what shape the battery is.

I only see the brand BionX

There is little other information on the battery, so first check which type of bike it is, then look at the charging connector and the connection to the bike. You can also check whether the light matches the picture on the website.

I see the brand and several type numbers

The brand is clearly marked on this battery: a Yamaha, with type number PASB2 but also B94.

I see a brand and an Art# as well

In this case you can search by the battery brand, QWIC, with article number BA00040. Don't search by the serial number: it is usually unique to one battery.

I can't find a brand on the battery

In this case the label shows no brand. Look for the brand of the bike or check the charger. The top of this battery does show the brand Giant, and you can see that it is a 36V battery, so look for further matches such as the connector, the charging port, and the shape and colour of the battery.