No love for SLA batteries?

[Lionstrike]

So I am planning my next ebike build and I am SERIOUSLY considering LifePo4. I've got some great ideas from Dogman and others on my first thread and I'm now debating between a 9c and a Crystalyte (probably 5304).

The choice of batteries has been a major question in my planning.

One of the recommendations made was a 9c 2806 with a 48v ping 20ah battery for my daily 25 mile round trip commute. It's definitely a candidate, and ebikes.ca seems to be a great shop to deal with. Ping batteries seem like they're easy enough to clamp an anderson powerpole connector on and get started.

Another idea is a Crystalyte 5304.... problem is... the batteries have got to be able to handle a consistent at least 40 amp draw.

Here's where I struggle. SLA batteries will probably handle that no problem. Sure... maybe 500 cycles out of them, but that's pretty much 6 months of use. Even replaced twice a year... that's only like $600 a year total for commuting = about 50 bucks a month. Doesn't seem like much when a single gasoline fill-up can cost at least that. And they're heavy, I get that (they are literally lead weights)... but super easy to install and set up. The fact that they have to be recharged immediately sounds more like a minor inconvenience.

LifePO4 seems ok... Pingbattery seeming to be one of the most well liked suppliers around here, but a 40 amp consistent draw on the batteries might be a bit hard on them don't you think? The C rating on most lifePO4 batteries isn't that great.

Lipo is almost totally out of the question for me. Massive cost. Very intensive and technical setup. Large chance for error in construction (seeing as I am a no0b and have only built one eBike so far) and many points of failure could render the pack useless.

So SLA to me while clearly not being the most superior option... isnt' all that bad. So... why don't folks like SLA?

 

[Ypedal]

Anyone who has used Lipo, at least once, will never want to hear the word SLA ever again....

It's like drinking fine wine at 200$ a bottle.. and being offered prison toilet ketchup brew..

But, hey, SLA is absolutely easy to live with.. fairly inexpensive and easy to get locally... yeah... it's an option.. but i will give up ebiking before i ever go back.

 

[snellemin]

I don't like sla for it's power to weight ratio. Charge time is also an factor. Lipo's for me. I can charge four 4s packs in parallel with no fussing around with the use of the FMA Powerlab 8 charger. Pretty much dummy proof setup when you get the parallel safe balancing adapters. All you really need to do, is check out your power consumption on your trip and/or have a proper V cutoff set. I only charge them to 4.1V per cell, so I can gain some more life cycles. How many more remains to be seen.
I could also do A123's, but size/bulk is an issue for me at this point.

 

[sangesf]

To get enough lead "weights" (as you call them) to enable 48v AND a 25 mike round trip, will be VERY HEAVY for one thing, and VERY LARGE as well, ESPECIALLY if you're planning on pulling 30+ amps from them.
You would need 4 - 28ah batteries at 20lbs per (80lbs total) at $80 a pop, which is $320 and that's at a BARE MINIMUM.

If you're not gonna go Lipo, then I would suggest a 48v 20ah (for lower draw motor) or 48b 25-30ah lifepo4 (for higher draw motor).

Alot of it depends on HOW you ride...
If you in an entirely hilly area then forget the SLA altogether..
If you pedal on starts at live in a relatively flat are then the 48v 20ah ping will work, even with the higher current draw motor.
30 or 40 amp pull continuous seems like ALOT..
You must wanna go really fast or live on top (or bottom) of a mountain.

 

[Lionstrike]

So lipo definitely seems like the reigning king. LifePO4 second... and SLAs pretty much get crapped on constantly.

I do have some hills in my area, but not terribly severe and not lasting for long stretches of road. Originally I said it was relatively flat land, but this was judged driving in my car and my motorcycle which made them almost unnoticeable.

Riding 10 miles on my ebikekit ebike the other day made me notice... THERE ARE HILLS HERE... the kind of hills that took 5-8 miles off of my top speed rather easily.

So then... would it be **reasonable** to take a 5304 Crystalyte and 48v 20ah Ping battery?

It's not that I want to go SUPER fast... it's just that I want 30 mph and I am 300 lbs.

 

[nuevomexicano]

So lipo definitely seems like the reigning king. LifePO4 second... and SLAs pretty much get crapped on constantly...

Just so you know, there are other lithium ion options out there apart from the LiFePO4. Chicagoelectricbicycles.com sells LiNMC batteries in 36V and 48V that are small and light (6 and 8 lbs). Ampedbikes.com's battery tubes are another type of light weight (36V12ah at 6 lbs.) lithium ion as well, though I'm not entirely certain which (maybe LiCoO2 or LiMn2O4?).

 

[wesnewell]

For 30mph @300lbs for 25 miles, you better go with a 30ah ping minimum. I'd go 40ah to be safe. Forget sla, you can't carry enough sla to handle it. You'd probably need 60-80ah. With lipo, I'd still go with 30ah to be safe, although you might get by with 25ah. I switched from sla to lipo about a month ago and would never go back to sla.

 

[nuevomexicano]

Also, I think the non-LiFePO4 lithium ion batteries that Chicagoelectricbicycles.com sells are the same chemistry as used in the Optibike.

 

[sangesf]

FWIW,

In PA. They classify an electric bike as a motorized pedacycle, (moped).
According to the quick research I did, it looks like you would need to get a VIN, register it, insure it and max speed is limited to 25mph.

So, 30mph sounds a bit out of reach for you. (Unless you want to register it as a motorcycle)
The lower draw motor with the Ping 48v 20ah seems to be your best bet.

 

[Lionstrike]

You just might have a lithium convert here.

By the way, I've got some time to work on this thing. I pretty much saw how jacked gas prices are now, and the fact that I only really live about 13 miles away from where I could charge and said that this is the last year I'll be a slave to oil. Every time I look at the gas station prices I say "get your hits in now... because this is the last year I am going to put up with the shi*."

That's advantageous to me on two grounds:

1) I could save up some coin for this project.

2) It gives me time to thoroughly research what I am doing.

But... if this project is to be a couple of grand (and it will be)... I only want to do this once. No "oops!" here.

Oh and BTW... I'd really be cool with 25 mph. I'd be o.k. with that... as long as it was not severely impacted by hills, and it could maintain that speed for a good number of miles. 30mph just gave me a little wiggle room in case I want a little more speed.

 

[sangesf]

Just to play devils advocate...

The whole VIN, register, insurance thing on an ebike, seems to be a little difficult to achieve... (more like an entirely incredibly PAIN in the arse!

Maybe consider a moped?

IF you decide to go with an ebike and can't register, VIN, etc and ride it anyways at 25-30mph and you get a cop who's bored (or hasn't gotten laid in months), he might ticket you for riding an unregistered moped, and that's just not fun.

 

[el_walto]

I'm not sure how much you can buy SLA for, but in general a ping battery will end up costing you less than buying and replacing SLA batteries.

You will not get 500 cycles from SLA. Especially if you are discharging it more than %50 of its capacity.

Here is a 33lb battery for you http://www.pingbattery.com/servlet/the-17/48V-30AH-V2.5-LiFePO4/Detail

 

[MikeFairbanks]

First, forget about putting SLAs on a rear rack. That's a bad option. Very heavy.

Secondly, if you can get them balanced in the frame, they work fairly well. They're still heavy, but the bike will still handle well.

If it's a tricycle, then SLAs are fine because weight isn't an issue. In fact, the weight stablizes the trike, keeping the rear wheels from lifting as easily in turns.

Don't forget that Ping Batteries are inexpensive compared to most, and although I haven't tried one, the reviews are overwhelmingly positive.

 

[Lionstrike]

LOL... a 300lb dude riding a moped would look comical.

I had this discussion with Dogman on another thread and I guess regardless of what the bike's capable of... if ridden sensibly the cops would pretty much give a dude a break. 30+mph on the road?.... uh... no. They'd probably get on my case for that.

But at roughly 25 mph... I can't really see cops having a problem with that... that's only marginally above specs. And what if I had downhill and a tail wind? That's a pretty easy 23 mph even with the 36v SLA I am using now.

By the way, that's another vote for the 9c over the Crystalyte motor then.

- Less amperage draw prolonging range.
-Kits from ebikes.ca come with a current limiting cycle analyst which would allow me to tweak the speed to keep it legal.

So... advantage 9c 48v 30ah battery?

 

[FMB42]

So... advantage 9c 48v 30ah battery?

Sounds pretty good.

BTW, can you tell us about your braking system (planned or otherwise)?

 

[sangesf]

If you get a CA, then a 20ah ping would work fine... Just limit max amps to 30 and you'll be just fine.
(Just watch out for them cops that haven't gotten laid in months!, hehe)

 

[MadRhino]

So lipo definitely seems like the reigning king. LifePO4 second...

Yep, good lifepo4 with hi C rate may be considerted almost equal to Lipo, except for the extra weight. Ping is far behind, and lead is dead.

The big Clytes sure love hi C rate batteries and big controllers, the 5304 is a beast when fed properly.

 

[Lionstrike]

Good points all... and as tempting as it is to make a bike that's just SICK we run into the prior problem... cops that haven't been laid in months. Limiting the amp draw to about 30 does have the anti-pissed off cop mitigating effect.

As for the braking system... I can't say yet. I haven't picked out a bike that's a good candidate for me yet, so I don't know what the stock braking power will be. I hear something about "Bulldog brakes" that seem to be solid. I guess if the stock braking system isn't sufficient, I'll look into those. We're probably not looking at disc brakes right now.

So... this 9c 20-30ah setup... major question here...

How does it take hills?

Because I hear that a Crystalyte Brute can take anything I can throw at it. If that's so... then that's a vote for Crystalyte 5305 over 9c 2806.

Which brings me back to my original confusion. So now I am almost certain that Pingbattery gets my vote... but 9c or C-lyte?

And I should mention, I have a 9c from eBikekit.com on my first build and it REALLY does not like hills.

Is that a vote for C-lyte?

 

[Ypedal]

Are you running your ebikekit at 36v ?

If you are, take the time to add a 12v to your existing bike and re-evaluate that hill..

It's all about watts man... both the 9C and the clyte will happily take 2000w, 3000w for short to medium periods depending on ambient temperature and for 4000w + then you seriously want to consider the X5.... but if you are currently making the hill on 600w ( Volts x Amps = watts..a 36v pack at 20 amps = 720w or so.. ) then 48v will bring you into 1000w\

Lighter bike, with more power is better than a heavy bike not being used to it's potential.. also less expensive and more fun to ride.

 

[MadRhino]

With a Ping battery, I'd go for the 9C. You would be frustrated not being able to up the amp on a Clyte because of battery limitation. Then, a 9C can be a fair climber if you chose a slower wind.

 

[Lionstrike]

Funny you should mention it Ypedal... my Powerwerx.com order just came in today... adding 12v to my current 36v pack and adding a "Doc Wattson" meter for instrumentation to see how it handles. This should be interesting.

So looks like with a pingbattery... 9c is the winner. Probably 2806, 48v 20ah... something like that.

So....

Stock 25a controller or upgrade to 35 amp controller and limit the current through the cycle analyst? About how much extra kick am I going to get from those 5 amps with a 35amp controller downgraded to 30a?

 

[sangesf]

If your amp draw is 35a max, then a 48v 20ah ping will work perfectly. No need to limit amps.

 

[FMB42]

As for the braking system... I can't say yet. I haven't picked out a bike that's a good candidate for me yet, so I don't know what the stock braking power will be. I hear something about "Bulldog brakes" that seem to be solid. I guess if the stock braking system isn't sufficient, I'll look into those. We're probably not looking at disc brakes right now.

I'm thinking that you'll definitely want to consider regen braking. Also keep in mind that disc brakes equipped bikes aren't all that uncommon or expensive these days. Another thing is that even the cheapest "no-name" brand disc brake units can often be converted to name brand quality disc systems. I, in fact, swapped out a "department store bike" front disc unit with a new, in the box, Avid BB5 setup for less than $40 USD (with excellent "stop on a dime" results).

 

[Evoforce]

I run Crystalytes with V-Power, Headway, and Ping batteries. I have no problems running these powerfull motors all day long on these LiFePo4 batteries. Just make sure you have enough amp hours and voltage. Minimum 48volts/20ah. While Lipo's lighter weight can be beneficial for racing, portable bikes and living on higher than ground floor etc, The initial cost for charging and battery maintaining equipment is higher and is not pug it in and forget it friendly. It also (maybe) will get only half the life cycles of lifepo4 so you need to factor that into the cost also. The Cycle Analyst can be your friend... Good luck

 

[MikeFairbanks]

Have you considered Worksman Industrial Bikes?

They can easily handle 300 pounds.

I have a trike (with a 36-volt SLA setup from EbikeKit.com) that pulls my 200 pounds (and the 100-pound trike) with ease up most of the hills around here. I do have to pedal on a few, but nothing that causes me to sweat.