SLA weight vs comparable power of lithium batteries

[Trackman417]

For all new people getting into ebike's and going straight to SLA batteries, just because they are cheaper, may want to see what they are up against.

I have a pack of 3 SLA batteries. All of which weigh pretty damn close to 30 pounds. Thirty pounds may not seem like its a lot, but it is. I am a pretty strong guy and these things are dense! Imagine taping and then filling two cereal boxes up to thirty pounds. I can't imagine a batter comparison.


While your at it, mount the cereal box weights onto your bike and see how much weight they add. It's alot! They are rated at 10 ah, but how ever i am only seeing two or three of those ten aH batteries.I have to carry a charger in the frame of my bike and make sure there is an outlet on the end of my ride. And when the batteries start to go, would you feel like lugging thirty extra pounds of weight? I DON'T THINK SO
I have been looking into getting LiPo batteries and right now the only thing that SLA going for it, is its safety. With LIPO, you cant just leave the packs to charge by themselves. SLA allows you to do that. I left my batteries charge in my garage over night while I went to go to sleep for the night and never once did I worry about those things catching fire.
Other than the safety aspect LIPO has bigger power to weight ratio (so I have heard) and you can use all if not most of the AH in the pack in one trip. An 8Ah LIPO battery, will get you 8Ah! 8Ah of LIPO will get you farther as well, because they are lighter then SLA.
Well thats my $.02 for the day. I don't have any pictures of how much smaller and how much LIPO is compared to SLA so sorry I can't do that, but if you guys could that would be pretty awesome!

 

[dogman dan]

Some more data.


sla battery 36v 12 ah. Usable Ah 6, weight 25-30 pounds Range at 25mph 4-6 miles Lifespan, 6 months heavy use 100-200 cycles. Possibly more cycles if used lightly.

Lifepo4 battery 36v 20 ah. Usable Ah 19.5, weight 15 pounds Range at 25 mph 22 miles. Lifespan 4 years heavy use or more. 800 to 1000 cycles. Possibly more cycles if lightly used.

Both packs exactly the same phyical size.

So half the weight, 4 times the range, 4 times the lifespan. Not terribly much more expensive, per usable AH. Lowest possible cost per mile.

Lifepo4 is very safe too. Plug in charger, go to bed.

 

[neptronix]

Actually an 8AH lipo will get you more like 7.5Ah ( you'll have to be kinda conservative at the bottom of the charge ), but yeah lipo rocks..

Compared to SLA, even headways would be a massive improvement. I measured 11lbs for 12Ah of 36v stuff.

I like how you have your SLA in what looks like may be a trash bag. Appropriate for batteries like that :lol: :lol: Actually they could be good for a small solar array as a buffer, or maybe a super extended life UPS battery

 

[Trackman417]

haha thank you Dogman for summing things up better then I would ever be able to!

Actually an 8AH lipo will get you more like 7.5Ah ( you'll have to be kinda conservative at the bottom of the charge ), but yeah lipo rocks..

Compared to SLA, even headways would be a massive improvement. I measured 11lbs for 12Ah of 36v stuff.

I like how you have your SLA in what looks like may be a trash bag. Appropriate for batteries like that :lol: :lol: Actually they could be good for a small solar array as a buffer, or maybe a super extended life UPS battery

I like keeping them in a bag when I am not going to use them for a couple months. SLA and batteries in general don't like being in the cold, so the batteries get a nice warm and comfy stay in my bedroom. The bag is also clothes, if you will, for the batteries because they look pretty damn ugly naked
Sooo I guess the only good things about SLA is what Neptronix just mentioned and how safe they are.
In the long run, SLA cost more than other "more expensive" ebike batteries.

 

[dogman dan]

Sla's still have thier place. Somebody who is never going to ride further than 8 miles, never faster than 10 mph, needs to charge safe in an apartment, but doesn't live on the second floor, and needs an ebike to cost less than $500.

But the situations were sla's are a good choice are as limited as the bike would be.

I had a real nice sla powered bike at one point. An EV global. Just two sla's were carried in the optimum location along the downtube of the bike. It was very slow, and very short range. But it had an onboard charger and was very easy to recharge. Just plug in and forget it.

But my needs were not to go slow and I needed 4 times it's range so I sold it.

 

[Trackman417]

Haha my SLA battery pack doubles the weight of my bike. It was a shocker to me. I just remember the day I took the batteries out and BOOM! All the weight my bike was carrying went away faster then a cupcake at a weight watchers convention (Jeff Foxworthy) =D. it's a shocker how heavy you think those little things are versus how heavy they actually are.

 

[dogman dan]

My first ebike was an Sla powered schwinn trike. Started with 36v 12 ah, and of course I didn't have enough range. Coming home, I have 14 miles uphill, but most of the hill in one big grade halfway home. Riding very slow to conserve, 3 sla's got me just to the top of the big hill, at mile 10. Adding a 4th sla got me to mile 12. Adding more, to 36v 24 ah, I got so heavy I started running out at the bottom of the hill! at mile 9! I'd simply gotten too heavy for even the milder uphills early in the ride.

By then the first pingbattery was in the mail thank god. I put it on a two wheel bike and ran the trike for awhile longer on sla's, never going more than 5 miles from home and staying out of the valley.

With the ping, I don't have to ride slower than 20mph to get 30 miles range.

 

[Trackman417]

Lol dogman I feel bad for your set of circumstances starting out. Haha I bet switching over was possibly the greatest thing since sliced bread for you 8) . Oh geez I just can't wait to actually GO somewhere without worrying about carrying a ton of dead weight on my bike. I may have moved to a house on top of that hill of I were you. Haha but what doesn't kill you makes you stronger. I guess you got A LOT stronger after that ordeal

 

[Trackman417]

BOOOM 72V 8000maH of goodness right there! more than half the weight and more than twice as much power!!
Lol I think this is the first forum on this sight that actually compares SLA and lipo.
Well if there is.... I didn't see any

 

[amberwolf]

There have been a few threads that compare them, and other chemistries, but that's ok.

I used to have 36V (then 48V) of 17-20Ah (mixed types) SLA on CrazyBike2. That's about 15lbs per SLA, so 45lbs (then 60lbs) of battery, and I probably didn't get half the Ah they're rated for even at about 1C or less, with my powerchair motor setup. I guess I got 12-15 miles with pedalling at maybe 12-15MPH. Cant' remember for sure.


Changed to "13Ah" 48V NiMH and a hubmotor and got maybe 20 miles at 18-20MPH; probably only got 8-10Ah out of them. I forget what they weighed, but I think it was half of the SLA.


Changed to "20Ah" 48V LiFePO4, same motor, and got 20 miles at 18-20MPH, about 12Ah out of it. Weighed about 20lbs? Poor memory at the moment.


Changed to 20Ah 48V "LiPo", same motor, and get at least 20 miles (haven't really run it down yet) at 18-20MPH, and that's only down to about 10-11Ah used so far, IIRC. I think it weighs like 17-18lbs?


Gonna test out some Turnigy 6s and (now) 3s packs, as 15s 3p (62V 15Ah) and see where it gets me, but first I have to verify the HV limit on my controller so I don't risk blowing it up. If it'll go higher I might try 72V 10Ah (18s 2p) instead. I don't know the weight yet.


But anyway, yes, there are definitely better batteries than lead. :lol:

 

[wineboyrider]

I tried to use the 24 12ah sla's that I got with my Ezip, but soon learned it wasn't enough power and range to go to the winery and back (relatively flat). When I first got my ping 36 12ah I fried my brushed motor and then fried another brushed hub sparrow motor. Lol THat's when I thought to myself" damn these batteries are bad ass." I use my old SLA's as a PSU for my lipo chargers now 8) 8) 8) 8) 8) 8) 8)

 

[Trackman417]

Haha thanks for forgiving me amberwolf. One thing I just don't like about these batteries is their sensitivity. I know they won't blow up from sitting around, but it's a matter of not paying attention when I'm using them and their voltage gets too low. It's the last thing I want to do haha. Get a huge fire in between my legs.
One quick question about zippy batteries... Is there a special connecter to connect the batteries together or do I need to peel the rubber around the bullet connecters?
Here's the batteries on hobbyking.
http://www.hobbyking.com/hobbyking/store/%5F%5F20837%5F%5FZIPPY%5FFlightmax%5F8000mAh%5F5S1P%5F30C%5FUSA%5FWarehouse%5F.html

 

[LegendLength]

Is there a special connecter to connect the batteries together or do I need to peel the rubber around the bullet connecters?

Just an note to be careful if you're peeling the rubber back from those connectors. You don't want them to touch

 

[Trackman417]

Heheh I found that out with SLA. Scared the shit out of me.
Who wants to hear a story?!
Well that's too bad your gonna hear it anyway.
My charger connecter to the batteries were all rusted out And this no current could through them to get to the batteries. No charging. I finally though why not use a plug and an outlet from an extension cord. Great idea except I put the prongs coming from the battery and I put the safer plug goin to the charger. I have a aluminum jacket around my bike and
When those prongs got into contact with the aluminum. Loud noise and it melted a hole through aluminum. Haha so I changed that around as fast as I could. Lesson learned
Would it make more sense to peel back the male wires only?