second battery

Pace

Member
I was hoping to go a bit longer before getting a second battery, but the original has dropped in it's charge capacity enough that I no longer have a consistent 10% buffer for my commute. I figure it's fully exhausted PAS1 range at the moment is around 25mi . The added drag of the winter tires I recently added is probably a factor too. I'm not positive, but I believe I have 100+ charge cycles on the original.

This will knock back the 'break-even' point of the bike purchase, but since switching to the Dash-based commute in september I've saved more than $800 in commuter rail tickets, so that covers the new battery and then some.
 

JoePah

Well-Known Member
Don't be discouraged.. Cold weather severely impacts battery performance. 100 cycles is nothing and you shouldn't see more than a 10% loss at this point. And if you can charge and store your battery in a warm room at night.

Have you thought about just buying a second charger for work?
 

PowerMe

Well-Known Member
This will knock back the 'break-even' point of the bike purchase, but since switching to the Dash-based commute in september I've saved more than $800 in commuter rail tickets, so that covers the new battery and then some.

Factor in the health and wellness benefits -- the enjoyment, the exercise, the stress reduction, the cardio benefit, and I think it's safe to say you've saved much more than just $800!
 

Pace

Member
Cold weather severely impacts battery performance. 100 cycles is nothing and you shouldn't see more than a 10% loss at this point. And if you can charge and store your battery in a warm room at night.

Have you thought about just buying a second charger for work?
Actually the cold weather hasn't really seemed to have much impact at this point, I've had more reserve left on some of the low 30's days vs the 50's days for example, it's a combination of factors (tires are one, more stuff packed in the panniers to account for weather variation, etc), but I could see the drop off in battery performance even a month ago.

I do have a second charger already... I've always needed that so I can charge both at work and at home. The commute is 40-42 miles round trip and I wasn't able to do that in a single charge after the first couple of weeks unless I eased off on my pace quite a bit. In the last month I haven't been able to use anything but PA1 without dipping below 10% reserve. That's in contrast to the first month I was able to mix in 30-40% of PA2 or higher with the same reserve.

So I'll have to start doing some battery shuffling, which was not totally unexpected.
 

Pace

Member
Factor in the health and wellness benefits -- the enjoyment, the exercise, the stress reduction, the cardio benefit, and I think it's safe to say you've saved much more than just $800!

Oh absolutely -- I didn't want to make it sound like the $ was my only consideration. I'm much happier on the bike than in the car or train.
 

JoePah

Well-Known Member
Actually the cold weather hasn't really seemed to have much impact at this point, I've had more reserve left on some of the low 30's days vs the 50's days for example, it's a combination of factors (tires are one, more stuff packed in the panniers to account for weather variation, etc), but I could see the drop off in battery performance even a month ago.

I do have a second charger already... I've always needed that so I can charge both at work and at home. The commute is 40-42 miles round trip and I wasn't able to do that in a single charge after the first couple of weeks unless I eased off on my pace quite a bit. In the last month I haven't been able to use anything but PA1 without dipping below 10% reserve. That's in contrast to the first month I was able to mix in 30-40% of PA2 or higher with the same reserve.

So I'll have to start doing some battery shuffling, which was not totally unexpected.

2 hours a day on a bike in winter.. That is some hard core riding.. Don't care if its an ebike!
 

Pace

Member
So after a few days of riding comparing my original battery w/ the new one, it looks like the original battery around 15% less capacity than the brand new one under similar riding conditions.
 

Shea N Encinitas

Active Member
So after a few days of riding comparing my original battery w/ the new one, it looks like the original battery around 15% less capacity than the brand new one under similar riding conditions.
How did you derive 15%, distance? Diags? - While it seems the diagnostic value for Ah capacity is probably not all that accurate (without logging charge & discharge) have you looked at the report for both batteries with a full charge? Without digging up that thread I recall that my factory battery was pretty low compared to the 2nd brand new one, but on the road I'm not seeing much difference. At any rate now you can spoil your batteries swapping with two bars remaining for example. BTW - The 36 volt 11Ah Bosch battery charges in about 2 hours when I leave a little in the tank. This affords me second rides in a day. :D -S
 

Pace

Member
I didn't use the Ah capacity from the diags as I read previously that it was not too accurate. What I did was take the average % value remaining for each battery over several rides and used that to calculate an approximate range if I used each battery to exhaustion... the old battery came out to a little less that 15% less max range. I used PAS1 throughout and my ride times and routes are very consistent at this point, as is the weight that I'm carrying, so there are not too many variables (maybe a bit on temp, but that's been similar for each battery). I should note that even the new battery is getting quite a bit less range right now than back in september: a combination of more weight (not me I'm less!, but I carry more stuff), studded winter tires, and colder temps all conspire to reduce the range.
 

JoePah

Well-Known Member
So after a few days of riding comparing my original battery w/ the new one, it looks like the original battery around 15% less capacity than the brand new one under similar riding conditions.

That sounds about right.. My stromer 36v11ah battery is a year old 2000 miles , around 200 cycles... And I'm down around 20%...all in perfect weather.

I will say that batteries degrade whether you used them or not.
 

Pace

Member
So if any of you are looking for ways to carry a second battery (Dash or Peak, but might work for some others), it turns out that the performance metro transit is pretty close to a perfect fit. I was looking for the smallest basic bag (already have panniers for storage) that would hold the battery and most trunk bags are fairly large.
(Link Removed - No Longer Exists)
 

Trevor Hayes

New Member
I definitely notice lower performance in cold conditions. When it's 50 out I can easily maintain 30 mph at PAS4 when my battery and legs are fresh. When riding in the 28-35 temp range I couldn't get the bike above 26mph. The range was noticeably decreased as well. That's what prompted me to get my 2nd battery - now I can use PAS4 for my whole commute.
 

wwjd

Member
This Leed frame bag works fine for me for storing my second battery. Plus, it allows one to put the battery where it belongs, at the bike’s center of gravity; which is one of the reasons why we bought these bikes in the first place. I have to put the battery in sideways in order for it to fit; and although it is a snug fit, it works perfectly for me. Plus, there is even some room left for storage. It looks better on the bike than in the picture. And the pictures of bikes shown with it on make it look like it will not work with the E3 Dash because of where the battery is mounted on the frame. But, believe me, it does.

I also tried lowering the frame-mounted battery a bit and leaving out the set screw, but the way the battery’s plastic is molded, it is made to fit the bracket without adjusting it any lower via the slots in the mounting bracket (so I am not sure what the slotting is for). If anyone does decide to get one, get the Large 21” model, that is, assuming you have the large bike as I do. You can determine your size by measuring the inside seam of the top tube from front to back. But I am not so sure that this will work with smaller frame bikes.
 
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