Stromer dual battery system with extra battery
“Compact” - 1146 Wh, "Midi" - 1188 Wh or “Maxi” - 1426 Wh.
Second battery. Triple the range.
Both batteries are available on board —
just switch between them!
One system for all Stromer models ST1–ST7 — plug & ride.
No changes to the bike’s wires or computer are needed.
The system includes a removable extra battery:
“Compact” (1146 Wh), “Midi” (1188 Wh) or “Maxi” (1426 Wh)
Long trip today? Just take both batteries.
Short ride? Leave the extra battery at home.
The battery is easy to place on the mount plate in one move.
The battery locks to the mount with a key.
It stays safe and cannot be taken easily.
When two batteries are on board,
just switch between them with the waterproof toggle anytime.
When toggle is down → original Stromer battery is working
When toggle is up → AccuBoost extra battery is working
Keep the toggle down → when extra battery is not on the bike
You can add and remove bags — battery and mount don’t block them.
No battery — no power on the contacts, in any switch position.
Cover keeps contacts clean and dry when no battery is used.
Looks natural. Just like it was made this way.
Ready for travel — bags and battery fit together.
Slim and clean — no parts sticking out.
Thin and elegant — keeps the bike’s perfect shape.
Check battery level easily — just press the button
Easy charging with the included fast charger
Easy setup at your place — ask about this option.
🚴♂️ Need more range? Continue using your Stromer battery — just add an extra one.
❔ Is your Stromer battery still working, but you feel the range isn’t enough?
❔ Are you thinking about getting a second battery — or even doing a full rebuild (replacing all Li-ion cells in your battery) — just to go farther?
💡 Our most cost-effective solution: an external battery that works together with your original Stromer battery.
Thanks to smart switching logic between the two batteries, they combine their energy for much longer rides.
⚡ The AccuBoost dual battery system is a smart upgrade that keeps your Stromer as it is — while giving you 3.5–4× more range, more power, and big savings compared to replacing all the Li-ion cells in your battery or buying a second battery.
⚙️ Stromer dual battery system — how is it built and how does it work?
Stromer dual battery system is a smart electronic system that is installed on your bike and allows you to use the original Stromer battery together with an additional removable battery.
The system lets you easily switch between the batteries at any moment using a toggle switch under the saddle.
Stromer dual battery system lets you use a powerful extra removable battery — “Compact” (1146 Wh), “Midi” (1188 Wh) or “Maxi” (1426 Wh) — to increase your riding range several times.
The original and extra batteries work in one system, but independently.
Both batteries do not share energy to each other and have different charge levels.
The extra battery is charged separately with its own fast charger (included in the set).
Both batteries give energy to the bike, but not at the same time.
You choose which battery to use at the moment by using the toggle switch under the saddle — everything stays under your full control.
One click of the switch — and the other battery starts working!
✅ Advantages:
System is fully compatible with any Stromer model: ST1, ST2, ST3, ST5, ST7 — no changes to the electrical system, bike computer and software are needed.
The additional battery does not replace the original one — it adds to it. Your original battery keeps working, and the energy from both is added together, up to 2409 Wh.
The extra battery is mounted on the rear rack, does not block bags, and can be removed easily.
You choose which battery to use at any moment as you want.
Switching between batteries takes just 1 second — one click of the waterproof switch under the saddle. One move — and many more kilometers ahead.
No compromise on design. The battery looks like part of the bike — it matches the Stromer style, not breaks it.
You can easy remove the extra battery anytime and leave it at home for short rides.
The original Stromer battery can continue to work without the extra battery as before.
The system is easy to maintain and simple to repair if needed.
Your Stromer stays a Stromer. Just with 3 or 4 times more range!
💶 Pricing & Payment
We offer a solution where you pay less — and get more.
The AccuBoost dual battery system for Stromer is not just an extra battery — it’s an investment in independence, freedom of movement, and long-term savings.
“Compact” (1146 Wh) — €895
(VAT 21% included)
“Midi” (1188 Wh) — €930 (VAT 21% included)
“Maxi” (1426 Wh) — € 1095 (VAT 21% included)
Prices include:
🛠️ Installation in Turnhout (Belgie),
🛡️ 2-year warranty for the whole system
No prepayment, no risk, no stress!
First, you test the system — then you pay.
We are confident in the quality, so we offer you 14 days to test the installed system on your bike before making a payment.
We trust the product — and we trust our customers.
🎁 Don’t miss your discount!
Check if there is a promo code where you found information about us —
and don’t forget to give it to us!
📊 Compare the real cost of extra energy for your Stromer
Here is a price-per-energy comparison of three common solutions. The results speak for themselves.
1. Buying a new original Stromer battery
Purchase of a completely new 983 Wh battery.
2. Full rebuild your old battery (replacement of all Li-ion cells)
All lithium-ion cells in the old battery are replaced. The remaining usable energy of the old cells is lost.
3. Installation AccuBoost dual battery system with 1146 Wh battery
An additional 1146 Wh battery that works together with your existing one — combining both capacities.
🔋 Purchase of a new original Stromer battery
Price of a new Stromer 983 Wh battery: more than €1500
Cost per 1 watt-hour of added energy: at least €1.52
🔢 €1500 / 983 Wh = €1.52
Cost per 1 watt-hour of total energy from both batteries: about €0.92
👉 We do not include the cost of the old battery, because it is available and still working.
Let’s say its remaining capacity is 650 Wh.
Then the cost per 1 watt-hour of total energy is:
🔢 €1500 / (983 Wh + 650 Wh) = €0.92
🔍 Conclusion:
❌ Buying a new original Stromer battery only makes sense if your old one is completely dead and you don’t have any working battery at all.
This option is very expensive and not cost-effective.
🔧 Rebuild of the old Stromer battery (replacement of all Li-ion cells)
Price of rebuild with all Li-ion cells replaced: about €750
Battery capacity after rebuild: 983 Wh
Cost per 1 watt-hour of added energy: about €2.25
👉 The old battery cells are thrown away, along with energy that could still be used.
The rebuild gives new energy, but wastes what was still alive.
🔢 €750 / (983 Wh – 650 Wh) = €2.25
Cost per 1 watt-hour of total battery energy after replacement of all Li-ion cells: about €0.76
👉 This is the cost per watt-hour for replacing all Li-ion cells.
🔢 €750 / 983 Wh = €0.76
🔍 Conclusion:
⚠️ A full rebuild (changing all Li-ion cells) is a good choice only if your battery has lost a lot of capacity, you don’t ride long distances, and you don’t want to add a second battery.
This option is not cost-effective, but it can still be useful if you prefer to keep your Stromer with just one battery.
⚙️ Stromer dual battery system with “Compact” 1146 Wh battery
Price of the full system with 1146 Wh battery: €895
Cost per 1 watt-hour of added energy: €0.78
👉 This means: the full system with a new battery costs the same per watt-hour as the rebuild of your old battery!
But — you can continue to use your old battery and its energy — and this is a big advantage!
🔢 €895 / 1146 Wh = €0.78
Cost per 1 watt-hour of total energy from both batteries: about €0.50 — uniquely low cost!
👉 We do not include the cost of the old battery, because it is available and still working.
Let’s say its remaining capacity is 650 Wh.
Then the cost per 1 watt-hour of total capacity is:
🔢 €895 / (1146 Wh + 650 Wh) = €0.50
🔍 Conclusion:
✅ This is the smartest choice if your current battery still works and has enough capacity, and you want to ride farther.
✅ The AccuBoost dual battery system gives you the same cost per watt-hour as a full rebuild, but you can keep using the energy of your old battery just like before — that’s a big advantage!
✅ It’s the most cost-effective way to add power and range without changing your Stromer.
📌 Comparison Result
The dual battery system offers the best price per watt-hour and lets you keep using your original battery.
It’s the smartest upgrade for Stromer owners!
🔧 Belgian engineering. Built for the future.
The whole system is designed and built in Turnhout, Belgium.
Full 2-year warranty.
The system does not change anything inside your Stromer — all wiring, the onboard computer, and software stay exactly the same. Your bike keeps all original functions.
We don’t buy ready-made batteries from online sellers — we’ve often found poor quality, incorrect specifications, or even fakes. Instead, we build every battery ourselves, using only original, tested, high-quality parts. This way, we know exactly what’s inside — and that’s how we can offer a full 2-year warranty.
We use only high-quality Li-ion cells from trusted brands like Samsung, LG, BAK, EVE, and Molicel, together with a reliable and proven battery management system (BMS)
Battery life is up to 800 full charge cycles (the best level possible) before capacity drops by 20–30%, if you follow simple charging tips.
Each battery is tested one by one for quality and safety.
Resistant to rain, dust, and UV sunlight.
Battery protected against wrong connection, overcharging, deep discharging, short circuit, and overheating.
📦 Dual battery system package contents
Removable AccuBoost battery (“Compact” 1146 Wh, “Midi” 1188 Wh or “Maxi” 1426 Wh)
48V battery fast charger (54.6 V, 4–5 A)
Water-resistant toggle switch between the main and additional battery
Connection cables with plugs
Adapter (restores your Stromer’s electrical system to factory condition in just a few seconds)
Protective cover for contact plate
Detailed user manual
For comparison: the original Stromer battery 983 Wh weighs 4.75 kg
🛠️ Installation and service with no stress.
No prepayment, no risk, no stress!
First, you test the system — then you pay.
We are confident in the quality, so we offer you 14 days to test the installed system on your bike before making a payment.
We trust the product — and we trust our customers.
Installation in Turnhout: takes only few hours
On-site installation at your location (including at home) is possible by prior arrangement.
We provide this service in Belgium, the Netherlands, Luxembourg, and in selected regions of Germany.
All parts of the system can be quickly removed by the bike owner, sent for repair if necessary, and reinstalled just as easily.
Restoring your Stromer to its original settings takes only a few seconds using the included adapter.
📞 Want to discuss your Stromer?
We don’t offer one-size-fits-all solutions.
A full replacement of all Li-ion cells in your Stromer battery is also a reasonable option. It makes sense if your original battery has lost a significant amount of capacity and you don’t plan to ride long distances. In such cases, keeping a single battery may be more practical. While this solution is much less cost-effective from a price-per-energy point of view, it can still be suitable for riders who don’t intend to use a second battery at all.
But if your battery still has enough capacity and hasn’t lost too much performance, and you plan to ride more without limitations, then the AccuBoost dual battery system for Stromer is without doubt your most cost-effective choice. It gives you more power, longer range, and saves you significant money compared to buying a new battery or doing a replacement of all Li-ion cells of your own battery.
We help you choose the right solution based on your situation, routes, usage, and budget.
If you’ve decided to go with our dual battery system, we’ll help you choose the right version —
“Compact” 1146 Wh, “Midi” 1188 Wh or “Maxi” 1426 Wh.
Contact us — and we’ll go over everything with you in detail:
E-mail: accuboost.info@gmail.com
Phone: +32 470 29 86 67