experiment 36v battery on 48v 13A TSDZ2 kit.

[neixian]

For experiment purposes, I fully charged my 36V battery today, it read 42V. And I connected it to my 48V kit, the display showed only one bar battery, which is expected.

However, interestingly, when I push the throttle, and lift the wheel in the air, it goes up to 40km/h and cuts off/on to maintain speed limit.

Seemly good, but when I rode it, I felt very little assistance even I set assistance level at maximum.
When I stop pedaling, and just use the throttle, the bike hardly moves.

It looks like that at 42V, which is very low if it were a 48V battery, there is very little torque.

Could it be that there wasn't enough discharge current? I had a 48V bike before, even when battery is very low, it still runs the same as at full battery level.

This battery is meant for a 36v 350w hub kit, which doesn't require as high current as a 48V 13A mid drive motor (Is this a 350w kit or 500w kit?), so the seller just used very low current grade cells.

Any ideas to help me understand this guys before I put an order for a 48/52V battery?

 

[E-HP]

docw009 provided you with the answer.in your other thread. Not sure why you started a new one when all of the context is in the other thread.

New member here, first question: 48V TSDZ2 kit on 36 Battery?

Hello guys, I am new to e-biking and this forum. I recently purchase a 48V 350W TSDZ2 with VLCD5 kit and read a lot about it here but couldn't find the answers I am looking for. What I am trying to do is to use this kit on my dual suspension MTB, to pair with a 36V 13ah battery I have...

endless-sphere.com

 

[docw009]

I think it's a useful perspective on 36V operation. Thanks.

No, I didn't say it would run like a dead turtle, but since the 48V version is a turtle to some of us, I'm not surprised by neixian's findings. In my case, I learned to live with the turtle in the TSDZ2, but I used to say the same thing about my TSDZ2 on a fully charged 48V battery, like turbo assist did nothing and I could barely tell the throttle worked.

In my case, I put in the OSF/embrusa firmware. I used their stock settings, so there's no extra power, but it's redistributed for lower pedal assist which made the TSDZ2 work better for me. In ECO mode though, I estimate I get 50 watts, as opposed to 100 watts on my hubmotors. It's a different ride.

If it weren't 0C outside and I hadn't just recovered (hopefully) from covid, I would go out and repeat neixian's testing with 36V on my TSDZ2. Maybe in a few days.

 

[E-HP]

Seems like with only a couple volts over lvc on a fully charged 36v pack, even a small amount of assist could cause enough sag to cut power, assuming lvc is set to 40v-41v for a 13s pack, unless the tdz doesn’t pull that much current.

 

[neixian]

docw009 provided you with the answer.in your other thread. Not sure why you started a new one when all of the context is in the other thread.

New member here, first question: 48V TSDZ2 kit on 36 Battery?

Hello guys, I am new to e-biking and this forum. I recently purchase a 48V 350W TSDZ2 with VLCD5 kit and read a lot about it here but couldn't find the answers I am looking for. What I am trying to do is to use this kit on my dual suspension MTB, to pair with a 36V 13ah battery I have...

endless-sphere.com

I thought this experiment would help someone who wants to mix batteries.

 

[neixian]

Seems like with only a couple volts over lvc on a fully charged 36v pack, even a small amount of assist could cause enough sag to cut power, assuming lvc is set to 40v-41v for a 13s pack, unless the tdz doesn’t pull that much current.

48v battery at low level would have voltage sag too, but I didn't realize any ride difference, even the battery level slowed 8%, on my old 48v hub drive.

And it didn't cut off. It ran, just extremely slow.

 

[neixian]

I think it's a useful perspective on 36V operation. Thanks.

No, I didn't say it would run like a dead turtle, but since the 48V version is a turtle to some of us, I'm not surprised by neixian's findings. In my case, I learned to live with the turtle in the TSDZ2, but I used to say the same thing about my TSDZ2 on a fully charged 48V battery, like turbo assist did nothing and I could barely tell the throttle worked.

In my case, I put in the OSF/embrusa firmware. I used their stock settings, so there's no extra power, but it's redistributed for lower pedal assist which made the TSDZ2 work better for me. In ECO mode though, I estimate I get 50 watts, as opposed to 100 watts on my hubmotors. It's a different ride.

If it weren't 0C outside and I hadn't just recovered (hopefully) from covid, I would go out and repeat neixian's testing with 36V on my TSDZ2. Maybe in a few days.

Slow as a turtle on a fully charged 48v battery?
How is that possible?
It is said to have 80nm torque which is much higher than my hub motor.

 

[E-HP]

48v battery at low level would have voltage sag too, but I didn't realize any ride difference, even the battery level slowed 8%, on my old 48v hub drive.

And it didn't cut off. It ran, just extremely slow.

If the 36v battery is fully charged to 42V, then the controller will cut power with a couple volts of sag. A fully charged 48V battery would need to sag 12 volts before the lvc cuts power.

 

[neixian]

Tka

If the 36v battery is fully charged to 42V, then the controller will cut power with a couple volts of sag. A fully charged 48V battery would need to sag 12 volts before the lv

Thanks for the clarification. Will experiment lower cutoff voltage when the programing doggle arrives. In the meantime I will buy a 48v battery.

 

[docw009]

OK. Test time. I set the LVC to 33 volts on my TSDZ2 and gave it a try. Battery temperature is about 48F, so performance down a bit. No other changes. Motor still configured for 48V.

My TSDZ2 conversion bike, a lightweight steel 10 speed from the 80's was topping off at 18 mph earlier with throttle on 48V. With a 36V battery charged to about 41V, this dropped to about 15 mph. In turbo mode, the pedal assist boost was mild, but I was still able to feel some assist in ECO though. Certainly pretty lackluster. Worse than turtle.

Need that 36V winding,

 

[neixian]

OK. Test time. I set the LVC to 33 volts on my TSDZ2 and gave it a try. Battery temperature is about 48F, so performance down a bit. No other changes. Motor still configured for 48V.

My TSDZ2 conversion bike, a lightweight steel 10 speed from the 80's was topping off at 18 mph earlier with throttle on 48V. With a 36V battery charged to about 41V, this dropped to about 15 mph. In turbo mode, the pedal assist boost was mild, but I was still able to feel some assist in ECO though. Certainly pretty lackluster. Worse than turtle.

Need that 36V winding,

Thanks for your test to help.

15mph is about 25kmh. So I might live with it until a 48v battery is definetely necessary.
Was it on the highest gear of your 10 speed?

Did you feel enough torque?

Thanks again.

 

[docw009]

If you didn't like your initial outing on a fully charged 36V, it will just get worse.

I didn't find it much fun either.

 

[neixian]

If you didn't like your initial outing on a fully charged 36V, it will just get worse.

I didn't find it much fun either.

Are you using OSF?

I think it can be tuned. The speed can be changed using bike gears, so the torque is everything here.

And current determines torque. You might have set the current too low.

Some say 18A is good, which is 720 odd watts on a 40V battery. But my motor says 48V and 13A.

Not sure if it will get cooked by 18A or not.