[#14][M2S] .. I FINALLY killed my ebike battery.. times 2..

Sic Puppy

I FINALLY killed my ebike battery.. times 2.. It is finally time to post a thread that answers the question that most novice ebike owners want an answer to: “Just how long can I expect the battery on my wonderful ebike toy to actually function correctly before needing to purchase a replacement unit?”. After all, the $600+ battery is by far, the most expensive component on a rear hub motor ebike. The motor comes in a distant 2nd at around $250.
I recently killed two of my batteries. Here is their past history:
BATTERY #1: 48volt/16ah.. Born on April 26, 2019.
Expired on Aug 23, 2022 (a lifespan of 1,195 days).
BATTERY #2: 48volt/16ah.. Born on July 11, 2019.
Expired on Sept 9, 2022 (a lifespan of 1,156 days).
Both of these batteries were originally M2S (ebike brand) https://shop.m2sbikes.com/? components. I would guesstimate that during the past 3+ years, I have charged each of these batteries at least 900 times, each time to 100% charge.
Battery #1 is actually a replacement provided by the wonderful folks at M2S because I thought the original item, delivered on April 30, 2018 with the rest of the 2018 KUSH (model, now known as 750FS) rear hub fat tire ebike had, at the 1-year mark, crapped out. Not so much “crapped out”, but rather experienced a reduced mileage-per-charge (40 instead of the original 55 to 60).
Back then I was not familiar with the idiosyncrasy known as “a full 4 seasons (summer, fall, winter, spring)” of battery fluctuation as a result of 100 degree temperatures, as well as 12 degree temperatures-- batteries do NOT like/appreciate either extreme. Therefore, as a result, the original power band is slowly reduced/degraded and mileage per charge suffers- for ever and ever. Both of the aforementioned batteries were down to 27 miles per charge, when used on the two M2S ebikes, at their final demise. However, when used on the ArielRider X52 ebike, only 14 miles per charge was attainable. Go figure.
M2S was really nice about my concerns that the original battery was defective. They just sent me a new battery (now known as battery #1) and I mailed the “defective” battery back to them. And that explains the one year time span (May 2018-April 2019) .End of that story.
Battery #2 came with my awesome 2019 M2S (brand) R750(model) rear hub fat tire ebike. I always refer to this ebike as WhiteyFord.
In regards to both of these batteries “stoppage”: they would charge up normally. However, when installed on the ebike and turned on, there would be an immediate (or very soon thereafter) shutdown of power. Since both of those batteries have an internal 40amp blade-type of fuse for protection, I checked that option . In both instances, the fuse was otay. That meant that enough of the individual internal cells had probably crapped out to then render the battery unusable.
You will find that there are companies out there who specialize in repairing these ebike batteries. What they will do is inspect/replace the defective cells, at a cost of around $400. That still leaves “X” number of the original cells still in use. What if, 3 months down the road, they decide to go titz up? Another outlay of $400 for replacement cells?? Just go ahead and buy a complete NEW replacement battery (my modus operandi). You will be ahead of the game in the long run. Plus, if like my situation, you have had many, many miles of usage from that original battery, then you have gotten your $$$ worth. Fer sure.
Let us proceed..
My daily ebike ride consists of 50 miles. I have been guilty of this activity since Summer 2018 (4+ years ago). Until the summer of 2020, the 2 batteries that recently keeled over were in daily use. To accomplish this distance, I always use 2 batteries-- 1 on the ebike and 1 stashed in my backpack. Depending on my state of mind, I will either stop at the 25 mile mark and swap out the units, or I will just continue riding until the first battery peters out and shuts down completely. I will then swap those rascals out. I may only need 15 miles from the replacement unit (to attain 50 total miles). I do this pretty much every day. If not every day, then at least 5 times per week. My batteries definitely earn their keep, so to speak. And, always tucked away in the nether regions of my lil peanut brain is “How long until this battery finally just keels over dead?”. Now I know. And so do you.
To be perfectly honest with you, I now have only 3 reliable batteries left with which to use for my daily 50 mile rides:
48volt/14.5ah battery, born on May 28, 2020 (842 days ago).
48volt/21ah battery, born on July 25, 2021 (419 days ago).
52Volt/18ah battery, born on Aug 5, 2021 (408 days ago).
As you can see, those 3 batteries are not nearly as old as the 2 deceased batteries (RIP). However, their time will come soon enough. So, what to do, what to do?? Order ANOTHER battery!! YaHoo!! Go Puppy, Go Puppy!! And, I did. More on that item later.
I guess that I keep straying from the intent of this particular thread subject, but that's otay.
Now, back on course:
Each of my batteries (and each of my 6 ebikes, too, for that matter) has a series of labels stuck to them:
Date of purchase..
Which ebike the battery belongs to..
The voltage/ah..
And, sadly, when available, date of death..

Each battery also has a color piece of tape stuck to the end cap for easy reference and as a place to jot down the miles used for that days ride. I also use black&white checkered duct tape wrapped around the charger input end of the two 52volt batteries. That visual reminder keeps me focused at charger usage time. The 52v charger also has that tape wrapped around its cable down near the connector. You can never to too careful when dealing with that part of ebike world.
As an interested ebike owner/potential buyer, you will encounter a never-ending barrage of ideas/opinions/expectations/encounters (like mine) as to the yin and yang of ebike battery maintenance. I, too, at one time, was one of those concerned folks. Then, finally, I just said SCREW IT. Nowadays I just give the batteries a 1 hour cool-down period (if from either 100 degree heat or 12 degree snow) and then I plug in the charger and let 'er rip, at 3amps, for 6 hours..
My daily modus operandi for my pesky batteries is to always begin the ride using the oldest battery on the shelf. After that decision, it is just a matter of which remaining battery to abuse. Remember, I had 5 batteries to choose from-- until the recent demise of those 2.
By the way, you will encounter much back-and-forth about “mixing” 48volt batteries/ebikes and 52volt batteries/ebikes. The reality is that it JUST DOESN'T MATTER. Sure, the “battery remaining” icon readings on your handlebar Computer Display Unit(CDU) might be off by a little, but not to worry. No smoke will appear from either the battery, the ebike motor, or the CDU. I used to actually get into the CDU menu and manually change the “voltage” option. However, when I realized just how minimal the the real difference was, I just left all my ebikes (two M2S brand 48volt ebikes AND the one 52volt ebike- a 2021 ArielRider X52) on the “48” display setting. Potato, potatoe.. Besides, my daily total miles ridden is really the only thing I care about.
Now, lets see.. You have seen just how long the top quality batteries in my ebikes have managed to survive my daily never-ending cycling escapades. By the way, the 2018 KUSH now has 21,000+ miles. The 2019 R750 has 15,000+ miles. The 2021 X52 has 8,000+ miles. So, I do get my $$$ worth out of my toyz. And herein lies another smattering of Words of Wisdom, as learned from my own interactions with aftermarket battery purchases..
I have purchased a battery from an overseas internet vendor on 2 separate occasions since 2019. Every instance was a really hard lesson learned. Should a situation occur, you are pretty much a screwed pooch as far as getting satisfaction/financial restitution from an institution ½ a world away. I sure learned some hard lessons. Ouch.
My initial advise to a potential battery buyer is to buy from an ebike company/dealer here in the USA. There is, most likely, going to be a few more $$$ spent for the purchase of the battery. You will, however, have piece of mind knowing that any kind of performance issue (from the battery) will be/should be taken care of promptly and with minimal hassle. After all, the USA company should have a decent Quality Control section.
I mentioned earlier in this posting that I had recently ordered yet another battery. The order was placed through this lady, Jenny Mao. The following is her EBReview thread, as posted on behalf of her company/employer: https://electricbikereview.com/forums/threads/reention-newly-upgrade-48v-25ah-36v-30ah-505l-interchangeable-for-ebikes-surface-604-ncm-rize-magnum-aventon.42705/ It was because of this thread, and the followup email communications with her concerning my potential purchase, that I went ahead and placed my order.
It is for the following: 52v/20ah Reention Dorado (it is the style of outer casing used on all on my ebikes), 18 inch battery length/14s4p Samsung 50E 21700 cell pack/5 holes/ 2 pin discharge port /DC2.1 barrel Charging Port&amp/30Amp BMS for max 1000w motor/with USB port/Battery+shipping cost to US $600, no extra customs. (I also had the option of buying other units, including a 48v/25ah battery for $700).
Jenny will offer you many options as to how you want YOUR new battery to be configured. Her company also offers JUICED (ebike brand) battery casings, so you JUICED owners have an option other than the JUICED website.
As for battery/charger connector items. Jenny offers the customer the choice of many different configurations. If you are interested in purchasing a compatible charger along with your battery purchase, their charger outer casing is finned aluminum instead of the cheapo plastic casing found on most chargers. Those plastic casings can get very warm, even hot. I learned a hard lesson on that matter very early in my ebike life (back in late 2017).
I also learned some interesting technical info from Jenny in regards to the charger output connector, specifically the DC2.1mm barrel unit. (it looks like a chrome .22 caliber bullet with a hole in the end); it is designed to be used by 1amp or 2amp or 3amp charger output. A 4amp or 5amp is considered to be too much of a strain on the 2.1connector/battery. So, while a 5amp charge will give your battery 100% in four hours, a 4amp charge takes five hours, and a 3amp charge takes six hours. Just goes to show you that life is definitely a trade-off.
In dealing with Jenny as it pertains to your particular ebike and its options: She will gather all of your information (ebike-wise) from you. She will then go research/find the options available to your situation. Quite the professional.
A word of advice from me: think of your ebike battery as an automobile gas tank. 48Volt/16ah= a sixteen gallon gas tank. 52volt/20ah= a twenty gallon gas tank. 48Volt/25ah= a twenty-five gallon gas tank. The 48volt-versus-52volt option is a trivial difference. Just expect to see 60volt batteries make an appearance in the future. That being the case, a 52volt battery will probably be compatible with the 60v unit. However, expect a 48volt battery to be too far out of parameter for a safe interaction. So, if at all possible ($$$ wise), go with the largest battery, both “volt” and “ah”.
By the way, I own the following aftermarket battery chargers:
Two 48v units (80%, 90%, 100%, and 1,2,3,4, or 5amp):
And one 52v unit ( also 80%, 90%, 100%, and 1,2,3,4, or 5amp) [I fixed this link on Sept.22]
A SideNote: this 52v charger is also available from LUNA:
All of these specialty chargers have a great price-point.

So, you can use/abuse the crappy doodle out of these batteries and, if name brand ebike company quality units, they will just keep on ticking-- for thousands of days.
As for the 2 piece of chit batteries that I purchased from DHGate.com website and from AliXpress.com website: STAY FAR FAR AWAY FROM THOSE RASCALS. Straight up 3rd rate/poor quality batteries from 3rd world countries. Lets face it, in a world that contains millions of ebikes (and their batteries), isn't kind of weird to see “7 orders/sold” on the 3rd world websites listing??
In closing, for those of you who only ride 20 or 30 miles per week, etc: you need to follow a different mindset than I do with my daily charging up to 100% on multiple batteries. For your situation, just charge your battery up to 70% or 80%, or so, and then top it off to 100% the day before/day of your ride. If you are interested in a very inexpensive volt/amp meter buy this item: https://www.amazon.com/dp/B093KTYG3G?psc=1&ref=ppx_yo2ov_dt_b_product_details I actually have this item installed on the handlebar area of 2 of my ebikes. I just use the “headlight” wiring. This only comes on when I use the headlight function. I highly recommend this simple device.
Well, I guess that's all. I hope that I have provided you with some good information.
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May I ask what your expected miles per battery are. Can you suggest a recommended aftermarket seller with Canondale Compatible batteries for a bosch performance class 3? As far a range, Not range per charge but your, range over the life of the battery. So not necessarily "born on date" of manufacture but number of miles you get over the life of the battery? Since my bike has an odometer, my Bosch 500, got exactly 1600 miles in 4 years. Thank you for your much appreciated buy new, buy American. It's details like this that indepth reports like yours make this site priceless. Thank you for taking the time for the great review brother. I wish you many happy miles of riding!

Sic Puppy

May I ask what your expected miles per battery are. Can you suggest a recommended aftermarket seller with Canondale Compatible batteries for a bosch performance class 3? As far a range, Not range per charge but your, range over the life of the battery. So not necessarily "born on date" of manufacture but number of miles you get over the life of the battery? Since my bike has an odometer, my Bosch 500, got exactly 1600 miles in 4 years. Thank you for your much appreciated buy new, buy American. It's details like this that indepth reports like yours make this site priceless. Thank you for taking the time for the great review brother. I wish you many happy miles of riding!
To Ebiker01; "3rd battery wen ?"
I haven't answered your posting because I'm not sure what (if any) response you are looking for. So...
Now, onward and upward.

To Contro Killerz;
First of all, thanks for the kind words. I have quite a few threads posted on this forum. Many of them are quite long-winded but, hopefully, 100% informative to the viewer. I judge the acceptance of those offerings by the number of views each receives. I get very few replies. However, if I do, like yours, they are mostly of a positive nature. That, in and of itself, is my best motivator. And what is my own personal all time favorite posted thread? This one: https://electricbikereview.com/forums/threads/3-of-4-my-2020-swift-torque-sensor-bottom-bracket-price-is-200-00.40097/ [WhoseYerDaddy?? I'mYerDaddy!!]
Sorry, I kinda got carried away.. On a stretcher.. Wearing a straight jacket..

In reviewing this response to your posting, I must apologize in advance for commandeering this space to provide too much extra info. I had intended to do a separate “battery item” posting over on the ArielRider forum. This posting allows me to kill 2 (or even 3) birdies with one shot. Plus, it is on the M2S forum. So, here goes.

As for your "Can you suggest a recommended aftermarket seller with Canondale Compatible batteries for a bosch performance class 3?" It is completely over my head. I have to suggest the lady (Jenny Mao) referenced in this (and other) post. She will provide you with quality up-to-date honest information. So, even if you chose to purchase a battery elsewhere, you will at least have all the pertinent data, thanks to Jenny Mao.

By the way, “born on date” refers to the day that the item is delivered to my front door, be it an entire ebike with battery included, or just a stand-alone battery purchase.
Your question: “number of miles you get over the life of the battery?” is a difficult item to pin down.
The 2 aforementioned, and now deceased (rest in peace) 48v/16ah batteries-- both M2S(ebike brand) items, received, by far, the most abuse of any of my many batteries. And they took a lickin' and just kept on tickin'. I did everything, and I do mean everything, wrong/incorrectly, practically from their day 1.
I would run the first battery down until it shut itself/the ebike off. I would then insert/use the second battery for the remainder of the 50 mile ride back to the condo. And, I did this almost daily, for 2 years. The horror, the horror. On a 98 degree/20 degree day, I would allow them cool down/warm up time of only about 15 minutes prior to hooking up the M2S-supplied 5amp charger.

And even then, I was apparently doing things back-azz-wards. I would connect the charger to the battery and THEN plug in the charger to the 110volt house outlet. It seems the correct procedure (as provided by LUNA website in 2022) is " Make sure you plug in your charger to outlet before battery. When LED is red it means the power is on."

So, you see, even 5 years (since Oct. 2017) into my ebike experience, I am still learning. A few sentences back, I mentioned the M2S-supplied 5amp charger. Their connector is the very commonly used DC 2.1mm barrel item. I charged both of those M2S batteries with the supplied 5amp charger(s) for 4 years. Never had a problem. The general consensus these days (in 2022) is that the 2.1 connector cannot adequately handle 5amps (or 4amps).

Nowadays, I have grown tired of chasing “the battery issue” and just charge all of my batteries, whether 48v or 52v, at 3amps and at 100%. That setting takes 6 hours to do a full charge from “1 battery” remaining icon (as seen on your ebikes cdu display). It is easy for me to keep an eye on the charging station (5 chargers total available for use) because it is located in a corner of the living room (1 bedroom condo) and only about 6 feet from my couch. Eazy Breezy..

Now, back to your question “number of miles you get over the life of the battery?”. I would have to guesstimate, even with excessive abuse, 17,650 miles per battery until the final demise of same. My M2S Kush @21,000 miles.. My M2S R750(WhiteyFord) @14,300 miles= 35,300 total miles and divide that # by 2= 17,650 miles per battery. I have used other batteries on these 2 beasts,too. However, I'd be splitting hairs to get down to that nitty of a gritty. But, you get a pretty good idea.
Also, to be fair, my riding, though skirting the foothills of the Rocky mountains, is 99.5% flat terrain. The bike paths I abuse follow alongside creeks, etc. So, if your own riding area consists of lots of climbing, you will have substantially lower “mileage” numbers.

You said your BOSCH battery has 1,600 total miles over a 4-year period. That gives you 11+ years to save up for a replacement battery. Either way, you will have definitely gotten your $$$ worth.
Also, I just noticed something on your posting: my Bosch 500, got exactly 1600 miles in 4 years. The word “got” caught my eye. Are you saying that, @1600 miles, your BOSCH battery has expired? If so, something is very, very wrong.

As for my “Buy in America” mindset, even that has limits/exceptions. Case in point:
AVOID THIS USA COMPANY: https://electricbikepros.com/produc...9&_sid=497828e02&_ss=r&variant=42056276312299
I made the mistake of attempting to purchase a 48v/20ah Reention Dorado (outer casing) battery from them. It was an absolute goat-rope of an experience.
In reality, they serve only as a “middle man” to some 3rd rate supplier located in a 3rd world country. Your order will be taken.. Your $$$ ($500, $600,etc.) will be withdrawn from your account.. And then, the fun REALLY begins.

You will wait. and wait. and wait. Eventually, you will email the company. They will give you the run around over and over. So, you decide to CANCEL the frigging order. Again, you will be given the same-o, same-o.. Excuses. Smoke and mirrors. Oh, and also, after making your purchase, you will eventually scroll down to the “cancel an order” section. There you will see “$100.00 cancellation fee imposed” for same.
What these varmits are doing is accumulating enough orders to make one large purchase/shipment from “over there”. In the meantime, you are treated to
CircusCircus as you attempt to actually take possession of the battery. Do not waste your time/energy in a pissing contest. You will finally (as I did) contact your credit card company/bank and file a complaint/request for full refund from this company. You will only need to supply a few back-and-forth emails from the guilty company to justify/verify the wrongdoings on their part. Your $$ will be refunded to your account (after a quick investigation). By the way, I am “debit card only” and I was still able to get my $500+ returned to my account. As for the company: they whined and complained (to me-via email), but not too much.

So, as I constantly state during my many, many EBReview posts: Learn From My Mistakes.. Or Not..

Finally, to throw yet another twist into this particular thread string, my “Buy from American Companies in the USA” is truly heartfelt, there is always an exception. In this case it is the aforementioned Jenny Mao https://electricbikereview.com/foru...es-surface-604-ncm-rize-magnum-aventon.42705/
This particular thread of hers is now (as of Oct. 2022) 13 pages long. This gal/her company is DaBomb. Her group of minions consists of some of the most popular/notorious/dubious/devious EBReview posters. And I am proud to now include myself in that convoluted gangsta posse.

I currently am awaiting the arrival of a 52v/20ah Reention Dorado battery from her. It will be used on my 2018 M2S KUSH(48v), 2019 M2S R750(48v) and the 2021 ArielRider(brand) X52(model)(52v). That means that I will be mixing the following batteries:
  1. 48v/14.5ah--14.5? What the hell is up wit dat?
  2. 48v/21ah
  3. 52v/18ah
  4. 52v/20ah
in no particular order on all of the aforementioned ebikes.

Since I always do 50 miles rides, and always carry 2, and sometimes 3 (for the ArielRider X52 ebike), batteries, I don't really pay much attention to the battery icon info displayed on my cdu. Instead, at the 25 mile (or so) point, I simply stop, take 2 minutes to swap out batteries, and proceed with the remainder of my 50 miler.
[SideNote: this is the low side-profile laptop computer backpack that I have been using for 3+ years: https://www.amazon.com/gp/product/B0732ZFF2M/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&th=1
It is perfecto for the 18” long Reeention Dorado battery casing. I have also mounted a CamelBak 100oz water bladder in it.]

I seriously considered purchasing a 60v battery in lieu of the actually purchased 52v/20ah unit. I emailed Jenny Mao and she responded that her company is still working on an acceptable BMS interface, so, for the time being, no, no 60v units . The 2 following YT videos will explain my “60volt” interest. But, I would only be able to use it on the 52v ArielRider ebike.
Here is a very interesting YT video(s). It concerns my X52 ebike, but it is saying ALOT about “mixing” different voltage ratings, controllers, etc in a very basic sort of way-- which is why I am so unconcerned about mixing battery voltages.
and then there is this one, too:

In regards to the X52 ebike: though I carry 3 batteries total, I do NOT utilize the aforementioned laptop backpack. Instead, I store the extra 2 batteries inside the frame installed seat/mailbox (yes, an actual mailbox). Too much fun.
Again, Contro Killerz (that name is BadAzz), I apologize for commandeering your posting to put out all of this info, but it had to go somewhere. Works for me..


New Member
Great info, thank you for posting it! Although your use case is far different from mine (you probably rode more yesterday than I have in the last two weeks), any real-world* battery info is great to have. And I tend to be a bit long-winded too, so I appreciate all the details lol.

*Probably more like dystopian world, from the point of view of your batteries haha


Well-Known Member
You had me until the USA source for chargers. One Grin charger could do it all and more for the $$ spent. But I’m glad those high return chargers have worked out for you. I have 3 that lasted less than a year and with relatively low use. I bought my first Satiator very soon after their introduction. My former shop sold them. Current pricing seems ridiculously high but in the long run, for me, they solved a weak link. Lots of chargers suck IME.