How to Wire a Battery for Electric Bike

Upgrading your traditional bike to an electric bike is a popular search query. A quick trip to Google will show that there are countless forums where bike owners ask about upgrading their bike and the best way to add a battery pack to their ride. Thankfully, because this modification is a popular one, if you have your heart set on upgrading your ride to an ebike, it can be done from the comfort of your own home. Check out these best practices and tips to ensure that you’re safely and accurately upgrading your bike to an electric model. And also that it is up to standard in comparison to the top-tier electric bikes on the market.

Let’s Start with the Warnings

Before you go running off to get supplies, you need to know that most ebikes rely on lithium-ion battery cells for power. Lithium-ion is a standard power source for most electronics including your computers, smartphones, and smartwatches to name a few. While they’re incredibly effective at powering devices, they do come with a few drawbacks.

What You Need to Know About Lithium-ion Batteries

While there’s a lot to love about these battery cells, you also need to know that they can also be very volatile and unstable. This is especially true if you’re not sure of the product quality. Poorly made lithium-ion batteries are more likely to malfunction when they overheat — and these batteries get hot quickly when in use especially for sustained periods. Also, be aware of the wattage and the level of power they can generate for your e-bike.

Wiring a Battery to Create an eBike

Depending on how comfortable you are with performing this modification or how handy you are with wiring, there are a few options available to you if you want to upgrade your traditional bike into an electric bike.

Buy an electric motor conversion kit

Hands down, the most user-friendly option is going to involve buying a conversion kit. There are a few different designs that will either offer front or rear wheel motor modifications. But these kits come with all of the equipment you need to upgrade your existing bike — including the battery — and provide step-by-step instructions which can usually be completed in under an hour.

An added benefit of using a conversion kit is that if you need help, you can contact the kit manufacturer for support. So, if you’re not comfortable going the full DIY route, we highly recommend that you opt for a conversion kit. These kits also include all of the wiring necessary to get your ebike up and running while also minimizing the total wires needed so that your finished product looks more like an ebike and less like a Franken-bike. Conversion kits are great ways to upgrade and install an electric motor on rear suspension bikes too.

Drawbacks of Conversion Kits

The only real drawback to using a conversion kit is that there’s always a risk that you buy a kit that’s not entirely compatible with your existing bike frame or riding habits. Maybe the motor isn’t powerful enough for your off-road riding or the motor or battery pack is just too large for the bike frame, leading to a poor user experience. So, always check to confirm that the conversion kit and associated pieces are compatible with not just your bike model, but your riding goals.

Building Your Battery Cells

We can’t stress enough, building a lithium-ion battery pack from scratch isn’t something you should attempt if you’re not comfortable working with battery cells, managing wiring, or are unsure of what parts you’re looking at when you sit down at your workshop desk. While this modification can be done in a fairly short time, it’s definitely the more clunky option and may require more trial and error.

To build your battery packs, you’re going to need 18650 lithium-ion cells. These are common cells found powering most consumer electronics and are the most frequently used lithium-ion version in battery packs — including ebikes. Note that you may need a few dozen to as many as several hundred depending on how much power you’re trying to harness. You’ll also need

Quality Matters

Also note that if you’re going the full DIY method, you want to make sure you buy quality lithium-ion cells. Experts usually recommend opting for name-brand models such as Samsung, Panasonic, Sony, and LG as these batteries offer consistent power output and have premium quality control standards that ensure they’re less likely to malfunction, explode, or catch fire.

The Tricky Situation with DIY eBike Batteries

While this isn’t an issue if you buy a conversion kit, people who go the DIY route are going to find that it’s easy to get lost in the wires. In other words, you can create an ebike that’s functional but very messy, with wires all over the place. You need to be intentional with your DIY battery and think about where you can safely route the wires on your bike frame so that it doesn’t pose a hazard or become impossible to fix if you need to repair the battery at a later date.

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