Help! Tongsheng TSDZ2 48v 500w to run on 36v battery

[Alanboo]

Hi All,
Hopefully a straight forward question, my wifes bike has TSDZ2 with a rear rack battery 48v 15ah, but after a couple of years biking she now says the back end of the bike is getting too heavy for her, i was wondering if i could simply put a smaller bottle type battery on the downtube but the only one i think will fit is a 36v 9ah would this still work with the 48v motor ? or if anyone has any ideas on other battery options.

 

[Nealh]

Lvc for the 48v controller will be wrong for the 36v battery, when the 36v battery hits 39/40v you will have cut outs and if not sooner in higher power modes .
The battery meter would also read empty nearly all the time.

You will need a 48v bottle battery or smaller footprint battery.

Not much space in the triangle for a battery so you may have a slight issue fitting something.

 

[Woosh]

The space inside that triangle may be too small for a conventional downtube battery. Cut a pie e of cardboard 36cm × 10cm to see if it will fit. If not, fit a 48v 10ah bag battery.

 

[Alanboo]

The space inside that triangle may be too small for a conventional downtube battery. Cut a pie e of cardboard 36cm × 10cm to see if it will fit. If not, fit a 48v 10ah bag battery.

On my bike i have the hailong battery which fits fine for me but it does not fit the bike in question, where could i find a 48v bag battery ?

 

[Alanboo]

Would i be able to downgrade the motor to 36V with the OSF so i can use the 36V battery

 

[Nealh]

Would i be able to downgrade the motor to 36V with the OSF so i can use the 36V battery

I don't think so
I use my 48v one at 44v ok, but it is only 4v difference in HVC so the battery meter doesn't show full charge for too long.

If you are set up for OSF one could give it a try or see if 36v firmware loads up and works.

 

[Sturmey]

If you connect the 48V motor to a 36V battery, the motor rpm will also drop proportionally so you end up with a normal maximum cadence that tapers off completely at about 80 rpm as the 36v version has a different winding, which I believe is the only real hardware difference between the 36V and 48V version.
This cant be solved by programming unless you try field weakening which would not be efficient. (afaik)

 

[saneagle]

Hi All,
Hopefully a straight forward question, my wifes bike has TSDZ2 with a rear rack battery 48v 15ah, but after a couple of years biking she now says the back end of the bike is getting too heavy for her, i was wondering if i could simply put a smaller bottle type battery on the downtube but the only one i think will fit is a 36v 9ah would this still work with the 48v motor ? or if anyone has any ideas on other battery options.View attachment 52781

It won't work. The motor will turn too slowly. You'd have to go everywhere in two gears higher, pedalling more slowly than is natural.

 

[Terol Jiang]

Hello, 36V TSDZ2 motor can use 48v battery, 48v mid motor must need 48v battery. you can use 48v 9Ah battery, but the BMS of battery need more than 30A, if not, it cannot drive the motor. Sure you only can choose downtube type battery, polly and bottle both ok.

 

[Woosh]

where could i find a 48v bag battery ?

E-bike Batteries | Electric Bikes from Woosh | electric bike sales & hire (wooshbikes.co.uk)

 

[Woosh]

Hello, 36V TSDZ2 motor can use 48v battery, 48v mid motor must need 48v battery. you can use 48v 9Ah battery, but the BMS of battery need more than 30A, if not, it cannot drive the motor. Sure you only can choose downtube type battery, polly and bottle both ok.

the LCD on the TSDZ2 is set for either 36V or 48V battery.
If you change the voltage of the battery from 48V to 36V, you need to reprogram the TSDZ2. You can't do that from the LCD's buttons.

 

[Terol Jiang]

if your battery is 13series 48v battery, the motor controller will control the ampers, so it canuse to drive the 36v motor.

 

[Woosh]

if your battery is 13series 48v battery, the motor controller will control the ampers, so it canuse to drive the 36v motor.

if you connect a 36V TSDZ2 to a nearly flat 48V battery, you can start the motor for a bit then it will pop up an error. If you connect a 36V TSDZ2 to a fully charged 48V battery, the LCD will just flash on/off. You can't even start the motor. If you connect a 48V TSDZ2 to a nearly flat 36V battery, it won't start. If you connect a 48V TSDZ2 to a fully charged 36V battery, it will work a bit then stops with an error. It's a waste of time.
Like all things to do with kits, you should follow manufacturers' recommendations.

 

[Terol Jiang]

We test this use Hailong 18650cells 13series 48v ebike battery. 48V battery can drive 36v motor. if other battery, maybe it cannot drive the 36v motor. the best choice is 48v battery drive 48v motor.

 

[Woosh]

We test this use Hailong 18650cells 13series 48v ebike battery. 48V battery can drive 36v motor. if other battery, maybe it cannot drive the 36v motor. the best choice is 48v battery drive 48v motor.

It's nothing to do with your battery is better than mine or mine is better than yours. If you sell kits, you should not advise potential customers to misuse the products in the first place. Manufacturers limit their warranty for a reason. Connecting a 48V battery to a 36V kit is unwise. Not only the kit functions outside its optimal zone if it functions at all, the change voids the guarantee and increase fire risks.

 

[Terol Jiang]

Oh sir, of course we do not suggest customer use 48v battery to drive 36v motor. we always insist use the matched-voltage battery to drive the motor. if customer has a 48v battery at hand, and he want to save money, want to use it to drive the 36v motor, we must let he know the limited conditions of the battery.

 

[Woosh]

Oh sir, of course we do not suggest customer use 48v battery to drive 36v motor. we always insist use the matched-voltage battery to drive the motor. if customer has a 48v battery at hand, and he want to save money, want to use it to drive the 36v motor, we must let he know the limited conditions of the battery.

Saving money by misusing your kit? Did you ride with a 48V battery on your own 36V kit?
this is the attitude that I deplore.

 

[Terol Jiang]

oh dear, what we do is use our professional knowledge to help customer solve problems. And we have a new type mid motor, it can work on 36v, 48v and 52v voltage, the display can show the instant working voltage. Of course the price expensive then normal type TSDZ2B/TSDZ2 mid motor.

Regarding the battery, you can purchase on Aliexpress.com, which supplier has oversea warehouse, then you can reduce the costs. the picture you show last time is pack type, also attached bottle and polly type pictures.