New batteries are no longer that complicated, but here is a guide on how to extend the life of your eBike Battery focusing on the Bosch range of products.

The Basics

The 300Wh, 400Wh, 500Wh & 625Wh PowerPacks used on Bosch-powered eBikes are amongst the most advanced batteries currently on the electric bike market. They offer a superior range, reliability & longevity compared to many other batteries. However, this all comes at a price; with a replacement pack currently costing around £600+.  Some people are put off by the price of a replacement battery, thinking that it will have to be replaced every other year, but this is just not true.

Bosch first generation display.

Bosch actually guarantees their batteries for 2 years or 500 charge cycles (whichever comes first). This doesn’t mean your battery will pack up after 2 years and 1 day. In fact, Bosch themselves state that the battery should be good for around 10 years or 1500 full charge cycles.  After 1500 cycles the battery will still work, but any battery will age over time so it will start to lose capacity and therefore not power your electric bike as far.

Also, it’s worth pointing out now that many people think that a part charge counts as a full charge cycle in Bosch’s terms. Unfortunately.. it doesn’t! If you just top the battery up a small amount, only this is recorded and will not be counted until there are enough of these partial charges to count toward a full charge cycle.

As a registered Bosh eBike dealer, when a Bosch-powered eBike visits our workshop we can use our diagnostics tool to read the battery itself. The Bosch battery is a very clever unit and records many different parameters, these are then saved within the system for us to analyse and consider depending on any issues presented. Also, we can tap into the system and see exactly how many ‘Full Charge Cycles’ this particular battery has had.  Furthermore, we can view many other variables within the Bosch software, for example – maximum/minimum battery temperature, charge state, usage, etc.

Bosch PowerTube 720wh battery.

Here are some of the most common questions we hear regarding Bosch batteries:

If your eBike came from us, we normally charge the battery fully just before letting it out of the workshop as we know you’ll be itching to ride it the minute you receive it. This helps condition the battery and gives it a starting point from which to gauge the rest of its operation. If you find it’s not fully charged, please charge it to 100% before riding. This applies to all brands of electric bike batteries too.

How often should you charge your Bosch eBike battery?

The new Lithium cells used within the Bosch battery packs are very advanced. Unlike the older style batteries where you had to completely discharge the battery and then fully charge it back up again, the new Bosch PowerPacks do not need this. In fact, it’s much better to just top up the battery after every trip. So if you have just cycled 10 miles on your electric bike, it’s better to top it back up to full when you get home rather than incorporating a few trips before charging fully.

Can I still clean my bike?

Yes, as with any bike – it is good to keep all components of your eBike thoroughly clean. If the exterior case or shell of the battery and motor is dirty, which will happen, this does not affect the performance of the internals. The best way to clean the battery is with a specialist bike cleaner, wet sponge (or soft paintbrush!), and low-pressure hose. A typical garden hose is perfect for washing away grime without applying too much pressure, once the area has been lightly agitated with the bike cleaner and sponge/paintbrush.

Bosch Performance Line CX Motor.

Although the Bosch batteries are weatherproof, it is never advised to use any sort of high-pressure jet/pressure washer on your bike. This pressure can force water into the battery case itself and potentially cause damage. It can also force water into other parts of your electric bike where you don’t want water to be (motor, bearing internals, suspension seals, etc.). So although it may be quicker to clean please don’t use pressure washers at all.

Will my battery range be affected if using an inverter from my vehicle or motor home?

No, you can use inverters to charge your electric bike – for example – from the cigarette lighter port in most cars. This can be handy if you are out and about or wish to charge on the move. But please make sure that the inverter itself is rated for the correct output for the Bosch charger. You can normally find this information on the inverter’s packaging or on a sticker on the inverter itself. The Bosch charger is designed for a rated voltage between 207 – 264 volts with an output of 42v.

The charger only charges the battery at a low 4 amp current; this is fine for most inverters and car batteries. Please check these values to make sure the inverter is compatible before plugging it in. One point to remember is that depending on the inverter itself, the battery may take a little longer to charge than if it was plugged into the mains.

Most importantly of all make sure the vehicle engine is running whilst the battery is on charge because it could drain your vehicle battery faster than you think.

How you can extend the life of your eBike battery easily:

In very simple terms, the harder you use your eBike the faster the battery will discharge. You can maybe classify this as the trade-off between fun and economy! Remember, the power of the motor can peak at 500w (depending on the specific Bosch motor) so it can draw power from the battery quicker and put a higher load on it the harder you push, and the assistance required.

The faster it discharges, then the more you will be charging it back up. This means that you could end up performing many more charge cycles than someone who is using their eBike lightly in the same time period. After a long period of time, the capacity of the battery will gradually drop. You could, therefore, be in the position of replacing it sooner if you’re riding your eBike close to capacity for the majority of the time (this is especially prevalent in de-restricted bikes).

We would recommend using an assistance level that works for you. Quite honestly you don’t ‘need’ to use the eBike flat out in ‘Turbo’ all of the time (even though it is fun!). The use of ‘Eco’ & ‘Tour’ modes for the majority of riding is generally more than enough, with ‘Turbo’ mode assisting on the very toughest of climbs or in tough conditions.

You can also utilise the eMTB mode on your Bosch system, which will vary the motor’s input depending on what you are putting in yourself. eMTB mode is always optimally adapted to you, the incline, and the terrain – regardless of rocks, roots, or steps. This will give you the most bike-like ride feel and will give you an even drain on your battery.

Bosch first generation handlebar display on EMTB mode.

Obviously, everyone’s fitness levels are different so you will need to work out what works for you, it is far too easy to hit ‘Turbo’ mode for the majority of your ride. The bike won’t go any faster (mph) but it will have more ‘grunt’, in fact, the eBike will only go as fast as you pedal, it’s just the amount of assistance the motor gives you that changes.

I’m putting my eBike away for the winter, will this damage the battery at all?

No, we know that some riders may not want to cycle through the cold, wet, and grim UK conditions found in the winter. You can store your bike away, it’s not a problem, however, there are some steps you can take to keep your battery healthy during these times.

Electric hybrid bike with bosch motor.

If you are keeping your eBike outside in a shed or garage, then it’s always best to bring your battery indoors. The Bosch batteries are capable of being stored in temperatures between -10 through to +60 degrees centigrade. But the cells don’t like to be stored in very low or very high temperatures. In fact, the best possible temperature for storage is room temperature – around 15-20 degrees.

Once in the house at room temperature, store the battery in a dry and secure place. Sticking it on a shelf in the kitchen above the kettle runs the risk of moisture traveling up from the kettle and into the battery case. So we probably wouldn’t recommend this as a location for storage! The perfect place is tucked away in a cupboard where it’s kept at optimum temperature, away from moisture, and where it’s not vulnerable to being knocked at all. We know it can make a very good doorstop, it’s tempting; but not good for your battery. Just make sure you remember where you left it when you come to want to ride it again…

Storage

When storing your eBike battery for long periods of time it’s best to keep the battery partially charged. If you store the battery completely flat then you run the risk of damaging the internals of the cells themselves. Also if you store the battery fully charged this can leave the cells under more pressure. So it’s best to keep the battery stored in between.

Bike battery being removed from a bike.

For the Bosch battery in particular the optimum charge state to leave it in is 60% (Or 3 LED’s lit on the battery level indicator). Try to check the capacity every 6 months or so. When the battery reaches 1 LED showing, then top it back up to 3 LED’s again. Many people think it’s best to keep the battery on charge so it’s always topped up in storage, but this is simply not the case. The Bosch charger won’t ‘overcharge’ the battery at all and does not trickle charge.

Will it harm the battery if I run it completely flat on a ride?

No – it’s never recommended to run the battery completely flat – but for longer rides, we know it can happen. The Bosch Battery is protected by its onboard BMS (Battery Management System). This means it’s protected for deep discharging, the BMS won’t allow the battery to run completely flat.

It may seem that you have no power left, but the BMS will have already shut off the power to the motor before it can hurt itself. We all know that the beauty of the Bosch drive is you can still ride without any resistance with the power switched off. On a side note here, if you are running lights directly powered from the Bosch motor and you do run out of power, the BMS will allow a small amount of power still to the lights so you will still remain visible!

I ride in very cold conditions during the winter, will this affect my battery life and performance?

The simple answer is yes. Similar to fuel MPG in a traditional car, Bosch says economy can be affected up to 30% in sub-zero conditions. So if you are consistently riding in these conditions it can really affect not just your range but will decrease the overall lifespan of the battery as well. There are certain actions you can take to prevent this, such as wrapping an external Bosch powerpack in a specific neoprene sleeve to keep it as temperature as possible.

Should I remove the battery when transporting my bike on the bike rack of my car/motor home?

Yes, this is strongly advised, put it in a dry & safe place inside the vehicle. It is less likely to get knocked and lessens the chances of the battery flying off the bike on the motorway if it’s not secured properly.

Bosch PowerTube 750 laid on a table

The best place to store the battery is under the driver’s seat, this means it’s out of the way and also shouldn’t move around too much. Wrap it in a towel to prevent any knocks. Do not leave the battery on your parcel shelf, if you end up braking hard, the 2kg+ battery is the last thing you want hitting you in the back of the head.

Also, by storing it in the car it keeps the battery from getting wet. Although the battery is rainproof, people don’t realize that if you’re traveling at 70mph down the motorway, the water & air traveling over your car is then doubled in speed as it wraps around the back of your vehicle. This means the battery could be being sprayed with water at around 140mph! This is stronger than a pressure washer and can force water into the battery and components of the bike itself.

I dropped my Bosch battery and the case is cracked, what shall I do?

If your Bosch battery (or any eBike battery for that matter) is damaged in any way, then it should be looked into being replaced. Even if it seems OK on the outside one or several of the cells inside may be damaged, this can then move on to other cells and the whole pack can become a ticking time bomb. The battery could seem fine and work but weeks later the effects of the damage could become apparent. The battery could heat up or even ignite in extreme circumstances.

Do not under any circumstances ship this battery anywhere. A faulty Lithium cell can reach temperatures of 1000+ degrees. It’s really not worth the risk, visit us in-store and have it replaced.

Bosch battery being charged.

So, how many miles can I ride on a Full Charge?!

Well this is the million dollar question we get asked over and over again. And to put it frankly, there is no one fits all answer to this question! You see, there are multiple factors at play which affect the distance capable on an eBike.

Bosch online range calculator.

Tyre pressures, total system weight, type of bicycle, tyre tread, battery capacity, motor system, cadence, environmental conditions, riding mode, average riding speed and even road surface choice will have individual and then combined factors on what you can get out of your Bosch motor & battery.

Bosch have a fantastic tool on their website, classified as Range Assist which can help you calculate the range for your next eike ride or tour. This takes into account all of the above factors, for you to determine by the sliding tools, and it will calculate the estimated range for you! Bosch Range Assistant – Here

When was your eBike last serviced? 

Something as simple as a brake pad rubbing can slow you down considerably. With the extra assistance on an electric bike, you may not even notice the extra drag. But the motor will be working much harder to assist you and therefore will drain the battery faster. It’s best to get your eBike serviced at least once a year to keep it in good shape which can pay dividends to battery health.

I think my battery needs replacing, what shall I do?

You should visit a Bosch dealer and have the battery capacity checked properly. We won’t take a meter near it, we will plug the entire bike into our computers and be able to give you a decision straight away if the battery needs to be replaced. On request, we can also print diagnostics reports for your records. When a new battery is purchased it comes with a new Warranty from a Bosch dealer, so be sure to keep the receipt of the purchase date safe. 

Remember if you treat your Bosch eBike Battery well, it will treat you well in return. We hope that this guide will help you to extend the life of your eBike Battery!