E-Bike Battery Care and Maintenance

Vern

Active Member
I have never had any luck caring for batteries. Laptops, tools, hobby batteries etc have all died on me way too soon. I think I tend to over charge things or something?? As I am consider buying an ebike, I am concerned that I will destroy that battery as well. I would like some specific answers to my situation. I desire to commute with my bike 2 to 3 times a week. My commute is 14 miles each way, 28 miles round trip. I can probably charge it at work. I am considering these three bike (Dash, Shadow, or a Neo--Neo Carbon or 650b)

Do I charge it at work when I get there, or let it run down a bit and just charge it when I get home? What is better for the battery?

Will the battery last longer if I don't let it run too far down, or am I reducing the life of the battery by charging it too often?

What do I do with the battery when I am not using the bike? Leave it on the charger like I do my power tools?

Is there any danger to charging these things or leaving it on the charger? I don't want to burn down my house or work for that matter??

Thanks for an advice,

Vern-The battery killer :-(
 
Vern,

The number one rule is never store the battery with an empty or low charge. That can destroy a new battery in no time. We see it every year.

Other than that, don't sweat it too much. The first few times you ride it, it's best to run it down as much as possible, then give it a full charge. After that, if you're riding regularly, give it a full charge as often as possible.

Avoid extreme temperatures when storing and charging the battery. The charger should be in an open, vented area to prevent overheating (this would break a charger instead of starting a fire). Most chargers have an auto-shut off. However, don't leave it charging for more that a couple days as the charger may start "topping off" any natural lose in the charge, which can shorten your range.

If you're going to store the battery for an extended period of time, I'd store it at about 80% capacity.

Charging at work isn't as important to battery life as it is to having the power to get home.

Regular usage ensures the best lifespan.

(All of this stuff applies to lithium batteries. Sealed lead acid plays by a different set of rules)

-Chandlee
 

Ravi Kempaiah

Well-Known Member
Excellent Question, Vern.

Chandlee, you seem to be really experienced with Ebikes and we appreciate your contribution to this forum.
As a researcher in the Materials Science industry, I know that there are 1000 different Lithium-Ion chemistry for Lithium-Ion batteries for e.g., LiFePO4, LiMn2O4, Lithium-Polymer etc.
The range and longevity of the battery also depends on the quality of the cells used and chemistry. More on this here: http://batteryuniversity.com/learn/article/types_of_lithium_ion

I know that brands like Pedego, Currie (eFlow and other top models) and Easy Motion uses high-quality Samsung or Panasonic cells but based on your experience do you know which chemistry is better for Ebikes?
What are the brands and chemistry to be wary of?

Also, any suggestions as what kinds of riding drains the battery/prolongs the battery?

Thanks
 

Court

Administrator
Staff member
Great question Vern and thanks for the stellar answer Chandlee... and supporting documentation Ravi ;)

I think you guys have pretty much covered it but I'd love to hear further thoughts on the best chemistry for ebikes (price vs. weight vs. life) and this thread reminded me of an adage that Ann, the owner of Alien Scooters in Austin once told me. She said "treat your ebike battery like a puppy. Don't let it get too cold or too hot and always make sure to feed it".

Your comments about long term storage at ~80% ring true (like when you get a new laptop or something and it can be turned on but usually isn't full and recommends charging) and I have also heard that doing a full cycle or two at the beginning of life is a great way to maximize capacity. I've also been wary of leaving items plugged in constantly, even if just for the vampire draw and potential fire hazard. One person suggested topping off the battery at least once a month, just to make sure it doesn't get too low. It sounds like when most batteries reach zero, the chemistry can change and form a "memory" which keeps it from reaching its full potential. I believe this is the case for Lithium Polymer and Lead Acid (unless it's a deep cycle Lead Acid).

Interesting aside here, I was listening to Elon Musk speak at SXSW in Austin 2013 and he explained that his company, Space X was trying to help Boeing with battery issues on the new 787 Dreamliner (which were catching fire). He suggested using smaller cells which are easier to regulate and maintain by keeping them separated. It seems like smaller cells might also be more resilient to having one or two drop off over time (see video ~23:00 minutes below). The downside to smaller separated batteries on ebikes might be weight... though I love how Faraday has designed their battery pack for the Porteur.


The life of a pack will be dependent upon, not the average temperature but the worst temperature at any point in any cell, so you really want to even that temperature out . . . The 787 batteries have very large cells, the battery cells are very big and they’re quite close together and there’s not enough insulation between the cells. So if one cell goes into thermal runaway and catches on fire, it’s going to cascade into the other cells . . . The approach we take at Tesla and SpaceX is we have smaller battery cells with gaps between them, and we make sure that if there’s a thermal runaway event which creates quite a bit of fire and smoke that it directs that fire away from other cells, so you don’t have this domino effect . . . The long term solution for having a battery pack that’s reliable and safe and lasts a long time is to reduce the size of the cells, and have more cells that are smaller and have bigger gaps and better thermal insulation between the cells . . . Lithium is getting a bit of a bad name here, Lithium is obviously the way to go. People have Lithium ion batteries in their cell phones and their laptops.

I also really liked when he said "[My biggest mistake is probably] weighing too much on someone’s talent and not someone’s personality. I think it matters whether someone has a good heart." (see video at ~52:00 minutes)
 

Ravi Kempaiah

Well-Known Member
Great question Vern and thanks for the stellar answer Chandlee... and supporting documentation Ravi ;)

I also really liked when he said "[My biggest mistake is probably] weighing too much on someone’s talent and not someone’s personality. I think it matters whether someone has a good heart." (see video at ~52:00 minutes)

Excellent message from Elon...!! He is truly great for the sheer reason that he took on some pretty big automotive giants when they all ganged up against him and tried to block Tesla's direct dealership.
I would really love to buy a model S but for that I will have to sell my kidney or something.

I also wanted to mention that vast majority of people are ignorant of Ebikes and Ebikes are some of the most underrated and under-promoted vehicles. They can be great solutions for 1000's of people in cities like SF, D.C, NY.
but it hardly gets any commercials and that's why one of the new startups (Riide) were able to get lots of funding in day one. They did excellent marketing and their product may not be top notch but I really liked their effort because they are doing it in the right direction.

Coming back, it would be wonderful to make this forum a resource-rich place. People can come here and learn about bikes, battery, maintenance etc.
Also, a source of motivation, those who are using it should post some pictures in different settings and DIY's etc.

Looking forward :)
 

Court

Administrator
Staff member
Great thoughts Ravi! This forum and ElectricBikeReview.com have become my full time job this year (aside from being with family). I'm very excited to help answer questions around the space and get the word out. I think reviews help in some ways but getting the opinions and feedback of people like you is great. It's wonderful to see you here :)
 
Ravi,

Great link and excellent observations. Addressing the battery chemistry question, I'd say pretty much all of the stuff coming from major brands is working well. You're right. There are thousands of combinations. Most of the Ebikes we've taken on are new enough that they shouldn't start degrading for a few more years (more than enough time to make it into SSD gen stuff). We've seen some problems with a couple of new battery types, but I'd attribute it to a factory issues instead of the actual chemistry. These are almost always easily warrantied. Court does a good job of pointing out who has good service.

Otherwise, I'd use caution in buying second-hand Ebikes with proprietary or unique battery casing. For example, my wife picked up an old Currie Enlightened series last year and we immediately replaced the battery with a new one from Currie. Unfortunately, the new battery was probably sitting in a warehouse and now her range is already close to nothing. Her only option is to repack with new chemistry and that can be costly. Fortunately, many of the Currie models still use the same casing and can easily be updated. (I'd also say that Currie's batteries became MUCH better after Accel purchased them.)

Buying batteries direct from China is going to be hit or miss. We do a lot a repairs on these, and it's difficult to say if the wholesalers are trying different companies or the quality control is simply poor. Unfortunately, QC in China is always going to be a problem, even for major brands (as we've seen this year). Again, the Ebike companies are quick to warranty any problems, but Chinese sellers usually offer short warranties and are difficult to follow up with. Do your homework before you buy.

In terms of getting the best range, well, that's a big question.

First understand that every Ebike is going to have a huge variation in range depending on the rider and conditions. SERIOUSLY. We're talking about 10 vs. 50 miles. Rider weight is a giant consideration. Hilly terrain (mountain biking) can seriously sap a battery. That said, large riders in mountainous terrain will still get great range provided they are doing their share of the work.

For example, yesterday I did some serious mountain biking with a 140 lb. rider and a 230 lb. rider. Both were on BH NEO MTB's and after an hour of hard riding the larger guy had only used 10-15% more battery because he was the more experienced of the two. Amazingly, I've seen a 300+lb. guy do the exact same trail on the exact same bike and use the same amount of battery! All he did differently was gear down and spin it out.

The important thing in extending range is balance your work with the motor's. With a PAS/cadence sensor, it's about finding a speed which your pedaling is starting to match or overtake the motor. This can make your range unreal with a bike like an e-Joe Angun which has a 16 amp/hr battery and a 12 mph level one PAS. With a torque sensor, maintaining a good cadence with proper gearing (as you should with any bike) is the key to good range. As Court frequently points out, this is also good for the freewheel.

Obviously, throttle bikes are going to require more attention and finesse. I find that just using the throttle for acceleration and then cruising really extends range.

Also, note that some of the smoother torque sensors are better for range as well (Bionx, Stromer, Eflow). You'll just get more of a workout!

Sorry for the giant response.
-Chandlee