12 v to 48 v boost converter for 48 v electric bike

[Akbar]

Hi ,
Is it possible to use 12 v to 48v booster circuits to power up a 48 v electric bike.
Currently my bike using 4 nos 12v 20 aAh battery in series to provide enough power.
Now i am looking to use one 12 v battery connected with 12 to 48 v booster converter. is it possible to run the bike this way ? And what the required ah capacity of new 12v battery?
Please help

 

[Harald Kapp]

It is generally possible. The effort depends on the current requirements on the 48 V rail (including surge currents when starting up the motor).
Note that on the 12 V side you will need to supply a bit more than 4 times the current on the 48 V side to maintain the power. This will drain your single battery 4 times faster.

 

[Akbar]

I think the motor rated around 250 watts.can I use 12v 80 ah battery for 30 km ride on single charge with booster ?

 

[davenn]

can I use 12v 80 ah battery for 30 km ride on single charge with booster ?

not enough info and too many variables to answer that

 

[Harald Kapp]

250 W equals approx. 25 A from 12 V assuming an efficiency of ~80 % for the boost converter.
Assuming furthermore that you can get ~60 Ah realistically out of an 80 Ah battery, that's 2.4 hours of operation at full load.
Riding 30 km in 2.4 hours sounds entirely possible, depending on the terrain (flat, hilly...).

 

[davenn]

can I use 12v 80 ah battery for 30 km ride on single charge with booster ?

Riding 30 km in 2.4 hours sounds entirely possible, depending on the terrain (flat, hilly...).

is one of the significant variables I was referring to

 

[Harald Kapp]

I know. Just wanted to get the discussion started.

 

[davenn]

I know. Just wanted to get the discussion started.

maybe you didn't understand .... I am in agreement with you

 

[Akbar]

250 W equals approx. 25 A from 12 V assuming an efficiency of ~80 % for the boost converter.
Assuming furthermore that you can get ~60 Ah realistically out of an 80 Ah battery, that's 2.4 hours of operation at full load.
Riding 30 km in 2.4 hours sounds entirely possible, depending on the terrain (flat, hilly...).

could you please provide me a circuit diagram ?

 

[BobK]

What do you expect to gain by going from a 48V to a 12V battery? Because you will be losing about 20% in the conversion.

Bob

 

[Akbar]

What do you expect to gain by going from a 48V to a 12V battery? Because you will be losing about 20% in the conversion.

Bob

to run a 48v dc motor on a sigle 12v 80ah battery.currently i having 4 numbers of 12v 20 ah battery connected in series and its cost me total around 150 us$ and its not long lasting 12 moth warranty only, if i go for single 12 v 80 ah battery its only cost me 75 us $ long lasting 36 month warranty and cheap .

 

[BobK]

OK. That makes sense.

To get the same run time, though, you should go to a 12V 100AH battery.

Bob

 

[Bluejets]

if i go for single 12 v 80 ah battery its only cost me 75 us $ long lasting 36 month warranty and cheap .

I'd be very wary of the claims of ah rating and warranty in a "cheap" battery.
Personally never seen a warranty extend beyond 12 months and even then, chockerblock full of conditions.
I doubt there would be any warranty if you are using it in the application described given the risk of deep cycling a standard battery (if that is what it is)

 

[Akbar]

I'd be very wary of the claims of ah rating and warranty in a "cheap" battery.
Personally never seen a warranty extend beyond 12 months and even then, chockerblock full of conditions.
I doubt there would be any warranty if you are using it in the application described given the risk of deep cycling a standard battery (if that is what it is)

Pls check the image stating warrenty here in india

 

[Bluejets]

You can be certain the warranty details will contain more than that which is displayed in any "offer".

Still, if you think you know better then go for it.

We try to be helpful here.

 

[Akbar]

You can be certain the warranty details will contain more than that which is displayed in any "offer".

Still, if you think you know better then go for it.

We try to be helpful here.

I already used a battery from them and I got replaced with extended warranty

 

[HarryA]

What do you all think of this converter?
https://www.amazon.com/dp/B01HEXJUX8?psc=1

Like Akbar I am interested in running a 40 volt motor off 12 volts (cordless chainsaw)

 

[Bluejets]

What do you all think of this converter?

I think that with 12v in you will get 12v pwm out.

 

[Harald Kapp]

Right, this is a motor controller only, not a boost converter.

 

[HarryA]

Thanks. Are there more efficiency circuits for DC to DC inverters than the class B amplifier type?
The type that uses a pair of transistors feeding a center tapped transformer.
For Akbar's 48 volts one would need about 68 plus volts into a bridge rectifier?