How to Carry a Spare Ebike Battery

Being able to choose the amount of effort you put into your ride is one of the big attractions of eBikes. If you’re commuting to the office in the morning, you probably don’t want to arrive looking like you completed a hill climb in the Alps. Equally, it’s great to be able to pedal and get your quota of exercise in whenever you choose.

A problem that many riders encounter is battery life. EBike batteries have limited range and as eBikes are heavier than standard bikes, you can easily find the fun runs out about the same time the battery does. 

There are lots of instances where an extra battery would come in useful. If you’re a serious mountain bike rider and take on remote trails, or you’re a road cyclist who pushes distances, an extra battery offers peace of mind and security. 

But as there is extra weight and an inconvenience to carry a second battery, we thought it would be a good idea to look at when it makes sense to take one and the best methods to carry it. 

Is Carrying a Spare Battery Worth It?

Before figuring out if carrying a spare bike barry is worth it, the first thing to do is calculate how many miles your battery will cover. The range eBikes can travel on a single charge can vary a lot, though there are manufacturer estimates.

Calculating Miles Per Charge

The terrain, traveling speed, weight, and most importantly the model of both the bike and battery are all factors. Other factors like the age of the battery and outside temperature can also have an impact. It’s not uncommon for riders with the same bike and battery to get different ranges from their eBikes. 

So with these many variables, you will always be working off a rough guide rather than an exact distance, but how can you make that educated guess? One of the main metrics for batteries is watt hours (wh). While there are many options both at higher and lower ranges, 500wh is a popular battery size.

Depending on the factors mentioned above, you could expect somewhere between 18 miles (28k) and 50 miles (48k) from a single charge. If you’re racing a mountain bike over rough terrain, then you will be at the lower end. If it’s a lightweight bike, being ridden in eco mode, you may well get past the 50-mile mark.

Bosch, one of the major battery manufactures, has a useful range assist guide that allows you to input your eBike and calculate how many miles your ride will last. While it’s helpful to see how the different factors influence the range, we would use this as a very rough guide.

Pedaling an Option?

If your battery runs out, you do have the option to pedal. After all, an eBike is a bike first and foremost, right? Well, depending on the type of bike you have, pedaling can become quite a chore due to the added weight and motor resistance.

If most of your riding is done locally and you don’t have large miles to cover to get home, then it might make sense to just run off one battery and accept a little extra peddling when you get caught out. If your riding takes you further and you have a long commute, or you’re ambitious with your day trips, a second battery might be a good idea.

Ebikes are getting lighter but there is still a large enough weight discrepancy to make you think twice about peddling any great distance when your battery has run flat. To give you an idea of the difference, one of Specialized more popular eBikes the Turbo Vader weighs in at 23kg (50lbs), while the similar but manual Sirrus range has bikes that come in under half that weight at 12.51kg (27.58lb). Not a huge issue if you have a short ride home, but it’s enough weight to have a noticeable impact on pedaling over longer miles. 

So, if you’re calculating whether carrying another battery is a good solution, you need to look at the current battery range against how you currently ride your eBike. Also consider whether you’re likely to carry on riding in the same way, or add more distance, or ride harder terrain in the future. If things are likely to change, it might make sense to get an extra battery early so you can take full advantage of it.

More Riding Possibilities

Another thing to consider is what possibilities a longer battery life can open up. As eBikes become more popular, their potential is starting to be understood. There are people using them for a wide range of purposes, including a replacement for cars for commuting, errands, and even food delivery.

While carrying the extra battery weight is a factor, it’s not the only factor to consider. An extra battery could well be a cost-saving and environmentally friendly option.

If you’re not riding a lot of miles and staying local, it probably doesn’t make sense to look at an extra battery. In the worst case scenario, you might run on flat occasionally and will require charging. However, if your mileage is high or even expanding then there are some interesting options available.

One Battery or Two?

Instead of buying a second battery, there is an option to simply replace your existing one with a model with extra range. Before you look at the best ebike batteries, there are a few things to consider.

All batteries will lose the capacity to retain their power based on how many times they have been charged. A lot of brands specify around 60% retention of charge after 500 charges. If you have a second battery, you can alternate between them and extend the life by double. This wouldn’t be the case with just one.

Another benefit of switching batteries is, if there is an issue with one, you will always have a spare. You can also charge one battery while using the other one. You can even leave one at another location, like an office or a friend’s house, to be swapped over.

While charging time varies, it usually takes between 5-8 hours to fully charge an ebike battery. But in most cases, you can usually top them up in a couple of hours. If you were running just one battery, you could top up your charge at places like coffee shops. We put together a list of places to charge your ebike on the go.

This ‘charge and go’ method probably wouldn’t be the ideal strategy for a lot of riders. This method relies on the good will of shop owners and does require some additional planning. It would be fine in an emergency but can be frustrating for a long-term plan.

How to Carry Spare Batteries

If you decide that a 2nd battery is worth it, the next question is, what is the best way to carry it? A standard ebike battery weighs about 7 pounds, so it’s worth considering the most effective way of transporting it around.

Where you battery sits is important for balance. Ideally, close to the center of the frame is best. However, while rear-mounted battery racks are also widely used.

Rear Racks

If you already have a battery in or on the frame, some weight at the back can actually help the bike weight distribution. There are specific rear mounted racks for eBikes, and some even have the capacity for two additional batteries. They also have additional luggage space on the raised platform which can be useful if you have other items to carry. The batteries are mounted centrally and there is the option for quick removal of the batteries, which is quite beneficial.

You will most likely want to pick up a small cover bag to help protect the batteries too. These are useful to have anyway for transporting and providing some protection as you move your battery around. The relatively low cost of covers compared to the cost of a battery make these a sensible choice.

Rear racks are quite low cost and simple to use. The only real downside is they will be attached to your bike for the most part. If you were only going to use a battery sporadically then these might not be the way to go. If you do travel with other bags regularly, you have the option of using one larger bag for your battery and other items. These can attach to rear racks and can also be taken off easily.

Rear Seat Packs

Rear seat packs are also a popular choice as they are waterproof and easy to remove. The position of the packs is quite good. The placement is close to the main weight of the rider so it’s a natural position for additional weight. The load capacity and size are particularly important in seat packs.

One popular saddle bag is the Rock Bros. The size of your battery is key here, as seat packs tend to be smaller than other carrying methods and struggle with the larger battery models on the market.

Frame Mounted Bags

Depending on how your existing battery is mounted, there may be options for a frame mounted bag. If your current battery is integrated in the down tube, a top tube frame bag would help with balance. These bags are easily removable and is low cost.

Frame bags are one of the most popular choices for a second battery if the top frame is free. If possible, you should look for a water-resistant model. While bike batteries are usually tough, you may want to add other items into the storage space. The Topeak Midloader is a popular choice and there are three sizes available, the largest being 6l. The bag has four connecting points that help distribute the weight of the battery over the frame. 

Security wise, frame bags, like seat packs, can be removed very quickly, which is ideal if you’re looking to take them with you when you stop riding. But what makes them great for you also makes them great for anyone looking to quickly steal them (see how to prevent ebike theft). It’s worth considering that with any of the lightweight bag options, you’re committing to carry them with you any time you park your eBike. 

Electric Bike Backpacks

While the battery weight will sit firmly on your shoulders rather than on your frame, there are some well designed, specialized backpacks for eBike batteries.

If you’re already carrying a backpack, these packs could be an option. Before you go off and purchase an ebike backpack, you’ll first want to make sure it large enough for your battery.

When choosing a backpack, a secure and comfortable fit is crucial. If you’re thinking of carrying a 3kg battery on your back for a long period of time, you’ll want to go for a test ride with the battery in it.

While some people remove the back plate to lighten the weight, we would definitely recommend keeping it in. If the bag feels too heavy, then look at alternative options to carry the battery rather than putting your safety at risk.

Evoc FR Trail E-Ride

While a lot of packs are aimed at mountain bikers, they can be used for any type of riding. The Evoc FR Trail E-Ride is a great starting point. It has a strong built-in back protector and fits the most common battery sizes. Even batteries that are larger than typical sizes such as Specliazed Levo can be fit in by removing the bash guard.

In our opinion, the Evoc FR Trail E-Ride is one of the best designed, specific eBike backpacks on the market with more battery room than most models.

Another popular pack with a capacity for large batteries is the Amplifi E Track 23. This eBike backpack also has a good back protector and is a little cheaper than the Evoc.

It’s worth noting that both of these models weigh upwards of 3lbs (1.4kgs). If you have a smaller, more typical standard sized battery, you might not need or want to carry the extra weight. There are plenty of lighter options such as the Ergon BA2 E, which are smaller and more suitable for standard batteries.

DIY Options

If you have a backpack already, there are ways to make some DIY modifications and save some money.

One option to secure your battery and stop if moving around is to use foam. The more tricky part of protecting your back can be achieved with a Motorcross insert plate. You can find versions of this which you can cut to size and they offer great protection.

As this is a DIY modification, you should test it thoroughly to see if it offers suitable protection for you. Ebikes move fast and batteries are heavy. It’s best to avoid taking risks if you’re unsure whether your back would be sufficiently protected.

Dual Battery Bike Options

There are some eBike models that do come equipped with dual batteries. This does make for a heavier ride, but it is an option.

One such bike is the Riese & Müller Supercharger. The Supercharger comes with full integration of two Bosch PowerTube batteries, having a total capacity of 1000Wh.

This bike is not cheap, starting at well over the $6000 price point. For this, you get technology that tracks each battery charge and selects the appropriate battery to run off at that time.

There are other less expensive dual battery models available, such as the E-Cells Super Monarch. While this model is much cheaper, there is a clear cost increase over single battery models which is worth considering. 


With the exception of riders who will be mainly staying in the neighborhood, we would recommend a second battery. A second battery gives you reassurance for your current riding and can open up new ways to use your eBike.

The options for carrying a spare battery vary. Whichever option you choose, you’ll need to know your battery measurement for getting the right fit.

If you’re a mountain biker, the Evoc backpack is a good choice, especially if you’re used to wearing a backpack for trail tools. Commuters might be interested in the rear rack options for the additional items you could take to the office. For most people, we feel the frame bags are a good balance. They are low cost, carry the weight in a sensible position, and are easily removable, which all together make a solid, versatile choice.