Verify compatibility before ordering. Due to shipping regulations, all battery sales are final.
We can’t say anymore than we love our Magnum E-bikes👍
10 Years of Premium E-Bikes | US-Based Support & Service
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Compatible with: Cosmo, Cosmo S, Cosmo X, Cosmo+
Genuine Magnum replacement battery. Direct fit for all Cosmo series models listed above.
Whether you're replacing a worn battery or adding a spare for longer rides, this is built to bring back your Day 1 range.
Not sure if this is the right battery for your bike? Submit a ticket or chat with us — we'll confirm compatibility before you order.
All Battery Sales Are Final - No Returns or Refunds
Need help confirming compatibility? Contact our support team before placing your order.
Compatible with: Cosmo, Cosmo S, Cosmo X, Cosmo+
Genuine Magnum replacement battery. Direct fit for all Cosmo series models listed above.
Whether you're replacing a worn battery or adding a spare for longer rides, this is built to bring back your Day 1 range.
Not sure if this is the right battery for your bike? Submit a ticket or chat with us — we'll confirm compatibility before you order.
Overall rating: 4.6 / 5 from 99 reviews.
We can’t say anymore than we love our Magnum E-bikes👍
Calvin S. 5/5 Verified
RIGHT PART FOR THE RIGHT BIKE.
Calvin S. 5/5 Verified
Perfect family bike! My kid loves it with the added MAC ride bike seat attachment. Very versatile and comfortable.
Sean M. 5/5
Excellent power, handling, seat comfort, value. VERY pleased!
Kathleen K. 5/5 Verified
GREAT BIKE … SMOOTH RIDE, PLENTY OF POWER, LONG BATTERY LIFE, GREAT SOUNDING HORN, RIDE USING TOURING SETTING, USE PEDAL ASSIST, WILL COAST FOREVER, TURN POWER OFF WHEN GOING DOWNHILL OR WHEN PEDALING IS EASY, GREAT FOR GETTING GROCERIES BY PUTTING MILK CRATE ON BACK RACK, WONDERFUL EXPERIENCE HAVING BIKE SHIPPED TO LOCAL BIKE STORE AND HAVING THEM ASSEMBLE AND TUNE_UP… GREAT SHIPPING OPTION!!
Tom R. 5/5 Verified
5 star ... Thanks for stepping up to the plate
Chris K. 5/5 Verified
Cosmo 2.0 is the fun way to exercise, go to farmers markets and do bike and breakfast dates etc with my husband of 40 plus years!! I sold my magnum cruiser because it was not a step through, in fact my best friend bought it !! My husband sold his ebike to her husband and he upgraded to the new this year magnum Bliss and he said it's his best ride yet!! Magnum e-bikes are reliable fun and the new colors are amazing! happy ebike riding everyone!
Connie U. 5/5
I received the item and I am very happy for your service
Neal D. 5/5 Verified
I have been using this bike to go everywhere and it has been incredible! This bike is really fun to ride and it beats sitting in car traffic! Used it for grocery trips, work commutes, joy rides; it's amazing and I highly recommend it for commuting and casual riding!
Cory R. 5/5
My husband bought me the Magnum Cosmo S and I absolutely love it. It is so much fun and a great way to spend time with the person you love.
Gina B. 5/5
I love this bike. The COSMO + is an easy to ride bike that allows me to ride further and enjoy the outdoors longer. The quality of the bike and the excellent customer service is top notch. Thank you Emily for your follow-up and excellent customer care.
Lori H. 5/5
I rented this exact bike while visiting my dad in Florida this summer and fell in LOVE!!! I had to wait a little bit before there were more in stock, but it was SO worth it! Customer service was phenomenal in helping me with a few hiccups in the beginning, but everything is perfect now, and I have been out riding everyday since! The best part about the pedal assist for me is that I have a bad knee, so I can still enjoy all the things I love about biking with a wee bit of help when I need it. Can't say enough great things about my Magnum Cosmo X!!!
Jeni P. 5/5 Verified
Store owner replied: Hi Jeni. Thanks so much for your purchase and becoming apart of the Magnum Rider Community! Love how you accessorized your Cosmo X.
I Love This Bike!
Jim H. 5/5
Store owner replied: Way to accessorize, your ride is looking great! Thanks for being part of the Magnum Rider Community. Happy Riding!
I'm new to Ebikes but have used regular racing bikes and mountain bikes for many years. I am a very fit 68 year old male. However, with age, I am starting to slow down and wanted some assistance in my bike riding. I researched many brands and models. I made the decision to stay away from mail order bikes as I read of many instances of bikes received missing parts or damaged through shipment. My local bike dealer had 3 Magnum S bikes and several other brands. The Magnum bike had more standard features that were optional items on the other brands. The Magnum also appeared to be built better and had a more powerful motor and battery. The next day the dealer only had one Magnum S left. This bike had a paint flaw on the down tube so after negotiation between myself, the dealer, and Magnum I was able to purchase the Magnum S for a $200 discount applied to the price point. I added a handle bar mount bottle cage and a different more cushy seat. The bike performs well and meets every need I have. I checked the accessories page on the web sight and noted there are no parts such as inner tubes, tires, batteries, controllers, etc. that fit the Magnum S. I then Emailed Magnum about this and they responded the same day and stated: "Due to the pandemics effect on the supply chain, we are still experiencing delays in receiving bike parts to our location in Salt Lake City, UT. Unfortunately, it could be anywhere from 3-6 months, but we are going to be restocking it." Because of the maker not having something as critical as batteries for this bike and other items like inner tubes, tires, and electrical components I cannot give this bike the 5-star rating it deserves. Fabulous bike with questionable support. Hopefully, I won't have to replace any of the out of stock items soon.
Dan 4/5
Excellent riding bike! I'm very happy with it and would recommend it.
Duncan S. 5/5
No toolkit for assembly, no warning about this, and now I have to wait extra few days just to wait for the toolkit before I can actually use the bike. Really bad user experience.
Kefei Z. 2/5 Verified
### Feedback I had a disappointing experience with my e-bike shortly after purchasing it. Within just a few days, the tire went completely flat while I was out on the road, leaving me with no choice but to manually push the bike back. When I took it back to the store, I was told that the original tube should be replaced with a better-quality tube with sealant. I ended up spending nearly **$200** on the replacement. The cost itself isn’t the biggest issue, but I honestly wouldn’t expect to run into this kind of quality/reliability problem within just a few days of purchasing a new e-bike. What I find more frustrating is that if a better tube with sealant is recommended for this bike, **why wasn’t that installed in the first place when the bike was originally sold?** It would have been much better to have the bike properly equipped from the beginning rather than finding out only after getting stranded with a completely flat tire. I’m sharing this as genuine feedback because I expected better quality and reliability from a new e-bike. Hopefully this can be looked at and improved for future customers.
Karthik K. 1/5 Verified
Excellent bikes, easy to put together. We love them and ride every day.
Steve P. 5/5 Verified
The battery arrived in timely fashion but it is not holding a charge. The old battery would only go down one bar on my daily commute to work and back. This new one drops down to where I have only one bar remaining. I tried calling your company and was told to file on line. I am very confused seeing as how I just received the battery
Ann T. 1/5 Verified
Perfect easy to install quick service thanks again
John G. 5/5 Verified
This eBike is so much easier for my wife to use. Much lighter and easier to get on and off the bike. She is a happy camper!
Stephen W. 5/5 Verified
worked perfectly and showed up fast
Valued C. 5/5 Verified
Not as nice as my Metro+
Robert B. 4/5 Verified
They displayed his self is very small as are the numbers
Jerry L. 3/5 Verified
Had the display for my Magnum Cosmopolitan ebike in stock. Quick shipment, greta price and fast delivery. Thanks Magnum
Eric O. 5/5 Verified
Excellent, fast service. New battery brought my 10 year old magnum Cosmopolitan ebike back to it's original glory. Thanks, Eric
Eric O. 5/5 Verified
I have not received the bike yet. I was told bike shop where it was shipped to will contact me when it is ready for pickup; but nobody contacted me. I do not know when/if I will receive my bike.
Vlad K. 2/5 Verified
My wife is happy now that she can get back to riding her bike and have control and information that she can see!
Art W. 4/5 Verified
Flawless transaction
Jeffrey P. 5/5 Verified
Send a bike that isn’t damaged.
Matthew W. 1/5 Verified
The batteries work great. Just wish the weren't so expensive.
Art W. 4/5 Verified
Great shopping experience
Stephen C. 5/5 Verified
My cosmo s are about three years old. I don’t know why you didn’t put stainless spokes. Mine are all rusted and have been inside most of the time. Also I have two bicycles
Dwight T. 5/5 Verified
Great bikes, I now have 4
Bruce M. 5/5 Verified
I’m grateful for Krysta and Magnum. I’m back riding.
Steve P. 5/5 Verified
Direct replacement, easy swap except the cord was about 2 inches shorter than the old one and had reposition inward toward bend in handlebars and rearrange feed wiring. ALMOST too short
Douglas B. 4/5 Verified
We needed a replacement Speedometer for our Cosmos E Bike. This replacement was a perfect fit. Delivery was as predicted. Pleased with the transaction.
Gordon H. 5/5 Verified
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Christopher K. 5/5 Verified
Great help getting the right part.
Brian D. 5/5 Verified
Incredibly cheap!!
Sean C. 1/5 Verified
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