48v 15amp sla battery pack & 1800w controller...

SnuffysBluff said:
...and motor.
Am I in trouble?

Insufficient data. I guess "1800W" means a 35A controller? So to support that load, the battery cells, connections, plugs, and BMS all must be capable of 35A or greater continuous current.

What do you know about your battery?
 
Chalo said:
SnuffysBluff said:
...and motor.
Am I in trouble?

Insufficient data. I guess "1800W" means a 35A controller? So to support that load, the battery cells, connections, plugs, and BMS all must be capable of 35A or greater continuous current.

What do you know about your battery?

I read the question as the battery is 48V with a 15A discharge rating. Then did the math you did, which seemed to indicate "yes" he's in trouble since he need 35A but only has 15A.
He could remedy that, if the controller could be programmed to a 15A limit. Then the answer would be "no"

So maybe enough data, but not clearly stated?
 
E-HP said:
I read the question as the battery is 48V with a 15A discharge rating. Then did the math you did, which seemed to indicate "yes" he's in trouble since he need 35A but only has 15A.

I see now what I didn't notice before-- that the battery in question is SLA. That means no BMS, but it also means it's very unlikely to be limited to only 15A of current (unless it's extremely small).

I guess the main risks here would be short range, short cycle life, and bothersome voltage sag.

I can't think of any reason to continue using SLA batteries in a vehicular application. Maybe if you can get them for free, and your vehicle somehow benefits from being heavy. Even then, nah.
 
Chalo said:
I can't think of any reason to continue using SLA batteries in a vehicular application. Maybe if you can get them for free, and your vehicle somehow benefits from being heavy. Even then, nah.

Ya, but people have their reasons, and as long as there's no safety issues. Anything with two wheels and propels itself is fun, and sounds like the motor and controller are destined for a future upgrade. :thumb:
 
Thanks folks for the replies.
Yeah, it's a bit of a reach but I got such a great deal on the motor/controller; I thought I'd try it.
I'm redoing my trike to get rid of the push trailer and hub motor. Backing up is a pain in the "tuchus".
Green bike.jpg
I knew the motor and controller were potentially too powerful for the 15a batteries but what the heck.

15a sla batteries.jpg
I guess it's either get big expensive lithium, bigger sla or buy a more compatible motor/controller.
The latter seems the logical route if y'all think a 500watt set up will still push this big vehicle around.

I've tried Chinese lithium in the past and haven't had much luck. I have two 48v inoperative lifepo4 batteries on the shelf.

But first, I just gotta see what happens when I get the chain drive setup going. 9 tooth motor sprocket and 74 tooth on the drive wheel.
 
Sorry for the unclear information..

4 12v 15 Amp Hour AGM batteries, dc brushless 48v 1800 watt motor, 48/72v 2000 watt 45a controller.
I forgot how precise the info must be for accurate diagnostics.

Not really concerned with run time or speed...torque is important as I'm 6' 4" @ 250 lbs and the trike is no lightweight either.
Just need to get to the tavern and work on my social skills. :thumb:
 
SnuffysBluff said:
Sorry for the unclear information..

4 12v 15 Amp Hour AGM batteries, dc brushless 48v 1800 watt motor, 48/72v 2000 watt 45a controller.

There should be no problem using those batteries. You won't get far before they run low, though.
 
Thanks Chalo...
I like these batteries and have many fun runs with my Grandkids on various of my builds.
I top off after even short run and these batteries last forever.
BikeGroupSm.jpg
The long recumbent was 48v 20a lifepo4 powered that Ping built in two parts for me.
inoperative now...may switch to agm if I feel like it.

The big rear wheel/small front wheel bike in the back has a geared front hub motor and had a Japanese lithium tube battery that is also long gone. Fun ride while it lasted.

I just don't trust lithium and they are too expensive.
Haven't bought lithium since 2010. Maybe the vendors or batteries are better now...I dunno.
 
SnuffysBluff said:
Thanks Chalo...
I like these batteries and have many fun runs with my Grandkids on various of my builds.
I top off after even short run and these batteries last forever.
BikeGroupSm.jpg
The long recumbent was 48v 20a lifepo4 powered that Ping built in two parts for me.
inoperative now...may switch to agm if I feel like it.

The big rear wheel/small front wheel bike in the back has a geared front hub motor and had a Japanese lithium tube battery that is also long gone. Fun ride while it lasted.

I just don't trust lithium and they are too expensive.
Haven't bought lithium since 2010. Maybe the vendors or batteries are better now...I dunno.

The three wheelers make me think Ben-Hur, but with an electric chariot.
 
E-HP said:
The three wheelers make me think Ben-Hur, but with an electric chariot.

Yeah, I get that a lot. :D

Just for fun I may hook up that reverse switch some of the newer controllers have.
 
Lesson learned...
One CAN have too much torque.

Test drove my trike with the 1800 watt chain drive motor,48v 2000 watt controller and 9 tooth to 74 tooth ratio.

Drive wheel (right) took over and the bike just wanted to run in left hand turns.

After fighting it for a hundred feet or so, it finally threw the chain.

I pedaled home and ordered a 500 watt motor, controller and 44 tooth sprocket from Amazon.

If this next attempt isn't satisfactory, I'll go back to the push trailer and rig a pully system to lift the heavy trailer up when backing.

This is getting >SOB< interesting. :bolt:
 
That trike should have a big slow front hub motor and that's all.
 
Aluminum.
...and there really isn't much weight distribution to the front.
It would probably just throw a bunch of gravel at the driver.

I suppose it's possible to build a steel set-up on the front, make a fender and buy a big and heavy hub motor.

Maybe next year. I'm having fun experimenting...

%22It's ALIVE!!!%22.jpg
 
Whaddia think about this?
https://www.youtube.com/watch?v=dOt42fO4QXU
I may give it a try.
Move the motor wheel up under the seat and jack it up a bit.
Should be able to utilize reverse also and keep life interesting for a while.
-------------
Waitaminut, waitaminut...Just lock in the trailer so it doesn't move should have the same effect.

Gotta go give it a try...film at eleven.
 
If anyone's interested...Here's what I have so far...
Green revise.jpg
BatteryBox.jpg
Motor&Sprocket.jpg
Bike insist on turning left due to the torque on the right wheel.
And the chain jumps off the motor sprocket.

Going to try a smaller 500 watt motor and controller.
If that doesn't work well, there is another thing to try before I go back to that !!!@#$%&!!! push trailer.

This is great fun, tho.
 
SnuffysBluff said:
Bike insist on turning left due to the torque on the right wheel.
And the chain jumps off the motor sprocket.

Going to try a smaller 500 watt motor and controller.
If that doesn't work well, there is another thing to try before I go back to that !!!@#$%&!!! push trailer.

This is great fun, tho.

If you put all the drive power on one side, you will get torque steer. Give it less power, you'll get torque steer with less power. It's still getting pushed on one side only, and it will still turn towards the unpowered side.

If you put a front hub motor on it, the motor will pull in the direction you point the front wheel. That's a good thing. You should try it.
 
SnuffysBluff said:
Going to try a smaller 500 watt motor and controller.
If that doesn't work well, there is another thing to try before I go back to that !!!@#$%&!!! push trailer.

This is great fun, tho.

Do I have to state the obvious?
  • Make an attachment to the legs in the back with small wheels.
  • Ditch rear derailleur
  • Beef up the black metal dropout plates
  • Install dual 5T QS 273 's

You may need to extend the wheelie bar out a little, but I'm pretty sure that solves the problem of pulling to one side.
 
Chalo said:
If you put all the drive power on one side, you will get torque steer. Give it less power, you'll get torque steer with less power. It's still getting pushed on one side only, and it will still turn towards the unpowered side.

If you put a front hub motor on it, the motor will pull in the direction you point the front wheel. That's a good thing. You should try it.
Of course you're right Chalo; my condescending friend. :D

It's just a matter of beefing up the integrated aluminum fork dropouts with steel and maybe it'll have reverse capability also.
I really don't want to change out the fork altogether as the steering is tied into it.

Other than the fact that I never liked front wheel power, it's really wouldn't be too tough to do.
I have some heavy duty fat BMX forks the will fit over the aluminum.

Not yet, tho...I'm having too much fun screwing up. :mrgreen:

And definitely not two wheel powered wheelies. (Funny; my son suggested that)
Unless the local law has changed...ya gotta have pedals or license...or pass as a disability vehicle.
 
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