52V 20Ah soft-pack battery install.

The biggest capacity battery that fits inside the frame of a folding eBike, is a soft-pack battery with Tesla cells.

If you have a MATE X, Engwe Engine or EP2, Vaya M1 or similar, you will no doubt have experienced “range anxiety” and wondered if there is a battery out there with even more capacity.

Instead of the 14.5, 16 or 17.5 Ah or capacity you currently have, you could make the jump to 20Ah. That’s where the soft-pack battery comes into the picture. It’s ideal for long rides with less range anxiety, and at a whopping 52V instead of the standard 48V, it also delivers that fully-charged feeling for longer. You’ve also got cells that are designed for use in cars, and are built to safely handle fast charging at 5A or higher without reducing the total lifespan. And let’s face it, you don’t want to charge a 20Ah battery at 2A – that would take most of the day! (but it’s stil recommended you do it every now and then to balance the battery).

Why a “soft pack”?

Most eBike batteries are built with AA-sized cells. Tesla cells are a different size, so in order to fit the maximum number of cells in the available space, it is necessary to sacrifice the hard metal outer-casing that is commonly used. Instead of the metal case, the battery is wrapped in heat-shrink vinyl to keep all the parts in place. The vinyl is easily damaged though, so please read the following list:

Things to be aware of:

• Care should be used when inserting and extracting the battery from the frame.
• Use the enclosed nylon strap to pull the battery out when needed. This essentially pushes it out from the inside, rather than pulling it out. See the attached video for instructions.
• Use the included adhesive padding to reduce vibrations and protect the vinyl wrapping as you slide the battery in or out of the frame.
• Additional vinyl wrap is included, and can be used to patch damaged sections or even to attach the head to the battery.
• It’s highly recommended that you just leave the battery in the bike and charge it via the opening in the side of the bike. This can make it impractical for those of you living in an apartment, where bringing the whole bike to a electrical outlet is not an option.
• The battery requires some assembly. The “head” is not attached to the main battery pack, and will require you to connect 2 wires.