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D-Man

100 kW
Joined
Nov 28, 2006
Messages
1,557
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best on my ESR sport scooter: 12 miles at 10 ~ 12 mph, sla 24v @ 18 ah
175 lb test rider

best on go hub bike: 18 miles at 12~15 mph, sla 36v @ 10 ah
152 lb test rider

The scooter batteries have since been replaced. I'd like another chance at a scooter range test-- plus i'd like to see how they do with a reconfigured Milwaukee lithium battery pack 28v @ 12 ah
 
I've got over 1700km and counting on my Dyno CB24V250 12Ah "Enduring" brand pack. Biggest single discharge was 85km/207Wh/8.8Ah. They were toast by about 6Ah.
 
Sorry, I mis understood.

Life span for the ESR scooter on the initial set of batteries was about 250 miles-- but I had some problems with some jumper connections.

The SLAs for the bike are still usable but I've switched to Li. I'd estimate that 600 miles are on the SLA batts.
 
I got over 400 miles on a pair of surplus Hawkers. They were still good when the controller blew last time. They were pulled out and used on another project.
 
I've got (3) 38AH 12V SLA batteries that have given me 350 miles so far, but I was figuring that I'm still breaking the bike in... they should go above a 1000 miles at least...
 
I've gotten 3000 miles on a set of 4 Hawker EP42s (Oxygen scoot). At that point my range was down to 15-20 miles. I've put these into another Lepton and they're still running strong.

On an Ego, I put 1000 miles on the CSB 34 Ah pack (24 V) that came with it. Then I added a 12 Ah pack on the rear rack, and put another 1000 miles on the bike. The bike still has 20 mile range.

I am absolutely fanatic about battery care. That means opportunity charging whenever possible (even if for 10 minutes), and the best chargers I can find (Zivans rock).

I have done some work with desulphators. They do work, but I don't have quantitative data on that. I'd like to try the high end units (I'm using a BLS 12/24B), but time and money prohibit more research at the moment.
 
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I've passed 1750 miles and I'm only discharging the batteries down to about 12.0 volts most of the time. By being so delicate with the draining I would not be surprised to get 10,000 miles out of them. I'm breaking a lot of other parts a lot faster than the batteries are wearing out. (like the poorly conceived transaxle)
 
Still in use at 1005 miles but the range has
gone down to about 5 miles. This is a tandem
used to transport children and cargo so the
load has been quite large most of the time
and I usually go top speed.

Roy
 
My friend has over 4000 km on a dual 14ah sla pack on a scooter type bike, I can verify as I was there for most of the time, but he used it as a commuter for around 5 months on a 25 km return trip, charging it at work. The batteries are pretty hooped now at around 20 km range.
 
My friend has over 4000 km on a dual 14ah sla pack on a scooter type bike, I can verify as I was there for most of the time, but he used it as a commuter for around 5 months on a 25 km return trip, charging it at work. The batteries are pretty hooped now at around 20 km range.
 
safe said:
I've passed 1750 miles and I'm only discharging the batteries down to about 12.0 volts most of the time. By being so delicate with the draining I would not be surprised to get 10,000 miles out of them. I'm breaking a lot of other parts a lot faster than the batteries are wearing out. (like the poorly conceived transaxle)

Sounds too optimistic -- seems most people get around 2000-3000 miles before capacity tanks if the pack is well cared for. Anybody here over 5000 miles on a single pack of SLAs?
 
At $400 for 8 $50 14ah batteries and 4000 km, that is around .10 per km + the cost of charging (not much) so if my small car gets 350km for $35 worth of gas that is the same cost at $.10 per km, what would you think is the cost per km for NiMH, or lithium?

Thanks.
 
For me, putting on 1400 miles a year, it takes only 4 months of e-biking to pay for the sla batteries. If I had nimh or a small pack of lithium, it would take close to 2 years of e-biking just to pay for the batteries. (based on fuel savings mpg)

Sla's 300 cycle.
Nimh 500 cycle.

If you don't drive a lot, you won't save a lot. Shelf life will get you before cycles will.
 
I got 1500 miles out of my no-name 36V, 12AH SLA pack.

Now I am at 1200 miles on my 36V 8AH NiCd pack from ebikes.ca and its starting to dump after about 8 miles. I think NiCd/NiMH packs with so many cells do not work well without some kind of balancing or individual cell monitoring.

I am ready to buy a new pack but trying to decide between SLA and some type of lithium.
 
I commute around 14 miles on a daily basis using 3 31ah 12v MK true gel cells on a Bikes At Work trailer for 6 months and still going strong.

John Morris
 
AlexK said:
I got 1500 miles out of my no-name 36V, 12AH SLA pack.

Now I am at 1200 miles on my 36V 8AH NiCd pack from ebikes.ca and its starting to dump after about 8 miles. I think NiCd/NiMH packs with so many cells do not work well without some kind of balancing or individual cell monitoring.

I am ready to buy a new pack but trying to decide between SLA and some type of lithium.

What was your original mileage on this pack, what discharge rate are you using? Curious because I have the same pack.

Thanks.
 
xyster said:
safe said:
I've passed 1750 miles and I'm only discharging the batteries down to about 12.0 volts most of the time. By being so delicate with the draining I would not be surprised to get 10,000 miles out of them. I'm breaking a lot of other parts a lot faster than the batteries are wearing out. (like the poorly conceived transaxle)

Sounds too optimistic -- seems most people get around 2000-3000 miles before capacity tanks if the pack is well cared for. Anybody here over 5000 miles on a single pack of SLAs?

Yeah but safe's batteries are 3x the capacity of normal 12ah e-bike batteries so maybe it is possible to get 10,000 miles. That is if he drives economically.

I expect a minumum of 4500 miles out of my sla's for my set-up. We'll see.
 
D-Man said:
Xyster: Sounds too optimistic -- seems most people get around 2000-3000 miles before capacity tanks if the pack is well cared for. Anybody here over 5000 miles on a single pack of SLAs?

Response: Yeah but safe's batteries are 3x the capacity of normal 12ah e-bike batteries so maybe it is possible to get 10,000 miles. That is if he drives economically.

I'm to 2,550 miles right now and I can say that after todays riding I'm sure that the batteries are in good shape. I managed four rides today where the temperature went from 60 degrees to 85 degrees, all with average speeds of about 24 mph, peak speeds of 46 mph and flat land speeds of 38 mph and a range of from 8-12 miles each. (so thats four half hour rides)

It all comes down to size... the maximum I'm drawing from the batteries is about 1C (40 amps from 38 Ah batteries) and at 1C that's pretty easy on the batteries. In theory SLA's can max out at about 5C (so for me my peak battery draw would be about 200 amps) so the battery would have to be EXTREMELY worn out to not be able to do that. After 300 cycles or three years I should be at 80% of "new" condition and so my peak should now be 80% of 200 amps which would be 160 amps. That's a lot more current than 40 amps... it's four times my controller limit.

I'm carrying as much in the way of batteries as a motorcycle (86 lbs) but most motorcycles will draw 100 amps or more. At 40 amps that's being really gentle on them. And I don't drain the batteries very much either and never drop below 12 volts.

What threw me off was the fact that TWO soldered Deans Connectors had failed and I only caught one the first time I looked. Once I caught the second failed soldered joint and fixed it the power came back.

Time itself will probably be the thing that wears the batteries more than my riding. The most you can expect in terms of time and age is about 3-5 years. I figure that the batteries are at least 2 years old and maybe three. (since I got them cheap) So I figure one more summer next year and then the battery will be down to about 60% of "new". That means that about 30 lbs of the battery isn't doing anything anymore.


:arrow: Doing the Math:

Current Required - 40 amps

Battery Ah - 38 Ah (call it 40 Ah to make it easier)

Maximum Current Drain - 5C

So we ask what percentage of the battery needs to be "gone" before the peak current can no longer be attained?

"New" condition peak power : 40 Ah * 5C = 200 amps

"Terminal" condition peak power : 40 amps

"Terminal" / "New" = 40 amps / 200 amps = 20%

:arrow: Conclusion:

The battery will need to have deteriorated to 20% of new before it can no longer fulfill the peak current demands of the bike. (for even a short time... actual sag is much worse)
 
I figure that the batteries are at least 2 years old and maybe three. (since I got them cheap)
So these batteries are "used?" Where did you get them at?
 
D-Man said:
So these batteries are "used?" Where did you get them at?

They aren't "used" but I suspect they sat in a warehouse for a year or two. I bought them online as a special "clearance" item. Three 38 Ah batteries for $138. Hard to know if the warehouse was hot or cold. If it was really hot then a summer spent sitting in a warehouse would add some wear to the batteries even though they weren't being used.

:arrow: Curent SLA mileage reading - 2,600 miles
 
Having excess capacity reduces the depth of discharge, which will extend the life of most batteries tremendously. Most battery chemistries are not very tolerant of overdischarge or even full discharge.
 
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