VGA VAX battery upgrade

[Langca]

Hi everyone. Sorry for English content, I have lived in Denmark just 1 year ago and bought a VGA VAX scooter. I have an original 48v 25ah battery. I plan to replace it with a battery with a larger capacity, like 48v 40ah or 50ah as shown in the link. Is there any problem? I'm not sure if it fits the original battery package. I hope the distance on a single charge can be 80km or more.
https://www.aliexpress.com/item/1005005 ... Redirect=y

[Landbo]

Hi.

I see at least two problems with using the battery you link to on your VGA VAX.

1. The interface to the scooter from the battery is not the same and assuming you don't have much knowledge of the electrical on a VGA VAX I doubt you can get them to work together.

2. There is so little information about the dimensions and weight of the battery you intend to buy that I could very easily get the impression that you are not getting what you are being promised down in China. I thought you should at least write to the seller and get data if I haven't already got you to abandon the project by point 1.

T. Hansen, who imported your scooter, cannot deliver another battery. However, you can have the cells replaced on your old battery here in Denmark for a modest sum of approx. DKK 5000 and up, if the old battery is bad.

May I ask how many km you can drive on one charge with the old battery and is it a 30 or 45 km version of the scooter you have?

Hope my answers are sufficient, otherwise you have to ask again, regards Leif.

[scootergrisen]

So far very few have done something like that and shared their experience on this board.
But go ahead and try if you want and share your experience with us.

The information on Aliexpress/Alibaba is very poor.
Perhaps partly because of chinese/english translation.

I'm guessing the dimensions written applies to the 20 Ah battery but not the 40 and 50 Ah battery which would likely be larger.
Picture says "Notes:Please note for size customization" so maybe they are able to build the size you need.

The pictures are showing Samsung 5000 mAh cells.
The price seems extremely low.

Might be difficult finding a pre-made battery that takes advantage of all the space.
If you want 80 km range and have the battery under the seat you would probably need to take advantage of all the space.
But You could also place the battery outside.
Someone building batteries might be able to reuse your battery box and put new and more cells inside.
I would like to do it but am unable to. But i collected information about it.

Also see:
viewtopic.php?p=31875
viewtopic.php?p=32150#p32150
viewtopic.php?p=30014#p30014
viewtopic.php?f=37&t=4329

[Langca]

Hi.

I see at least two problems with using the battery you link to on your VGA VAX.

1. The interface to the scooter from the battery is not the same and assuming you don't have much knowledge of the electrical on a VGA VAX I doubt you can get them to work together.

2. There is so little information about the dimensions and weight of the battery you intend to buy that I could very easily get the impression that you are not getting what you are being promised down in China. I thought you should at least write to the seller and get data if I haven't already got you to abandon the project by point 1.

T. Hansen, who imported your scooter, cannot deliver another battery. However, you can have the cells replaced on your old battery here in Denmark for a modest sum of approx. DKK 5000 and up, if the old battery is bad.

May I ask how many km you can drive on one charge with the old battery and is it a 30 or 45 km version of the scooter you have?

Hope my answers are sufficient, otherwise you have to ask again, regards Leif.

Hi. Thank you for reply.
First, I am using the 30km version and The battery I'm using can run 50km per charge. but after I went on a trip for 1 month and came back, it only run about 35km.
I admit that I am new to electric scooters and have no skills in the electric profession. so I have a lot of questions.
As for buying batteries, it seems the old link doesn't give much information. so I looked for other brands and got some replacement products. Liitokala is also a famous battery manufacturer and has its own website, so it can be trusted.
https://www.aliexpress.com/item/1005002 ... Redirect=y

If I buy a battery, now is what I will have to deal with.
A battery pack will have built-in bms, so I don't know if I can use it right away or if I have to use the bms in the old battery. If so then I have to remove all the old batteries cell away with old bms and solder the new battery pack to the old bms.

[Langca]

If I can ignore the old battery, I can just buy a waterproof case for the new battery. But here comes another problem. Because the vga vax uses a strange chogori connector, I don't know if it's possible to use a p-type connector instead of the chogori to discharge power from the battery to the scooter.

[scootergrisen]

I guess you can do it any way you like.
But i would keep the connects original.
Buy a new box and Chogori and P connector like the original box.

If you changed the connector on the scooter to something else then you would not be able to use an original battery.
Unless you made an adaptor.

The Chogori connect is able to be used for both charging and discharging.

[scootergrisen]

Maybe like so.

battery_modified.jpg (112.2 KiB) Vist 4000 gange

[Landbo]

Hi. Thank you for reply.
First, I am using the 30km version and The battery I'm using can run 50km per charge. but after I went on a trip for 1 month and came back, it only run about 35km.
I admit that I am new to electric scooters and have no skills in the electric profession. so I have a lot of questions.
As for buying batteries, it seems the old link doesn't give much information. so I looked for other brands and got some replacement products. Liitokala is also a famous battery manufacturer and has its own website, so it can be trusted.
https://www.aliexpress.com/item/1005002 ... Redirect=y

If I buy a battery, now is what I will have to deal with.
A battery pack will have built-in bms, so I don't know if I can use it right away or if I have to use the bms in the old battery. If so then I have to remove all the old batteries cell away with old bms and solder the new battery pack to the old bms.

Ok with the number of km you can drive on one charge.

Yes, Liitokala is one of the better Chinese battery manufacturers.

But if you want to buy a battery in China to build it into a battery case for the VGA VAX, you should definitely buy one with 18650 cells that are the same size as the ones in the original battery and not one with 21700 cells that are greater mechanical. If you don't use the BMS that is in the original battery but the one in the China battery, my guess is that you will have a lot of difficulty integrating your new battery with your VGA VAX. It is not only a matter of whether the connectors mechanically fit together, but also of which electrical signals go back and forth between the battery and the scooter's electronics.

Regards, Leif.

[scootergrisen]

The original system have a smart way of turning on the discharge.
Normally you cant discharge from the battery if you connect something to + and -.
Like you cant measure the battery voltage just by connecting a multimeter to + and -.
viewtopic.php?p=28342#p28342
viewtopic.php?p=30012#p30012

There is a wire in the center of the Chogori connect. Thin yellow wire. When it gets connected to - the battery can be discharged.

If you buy that battery from the website the BMS does not have that function.
So I think the DC to DC converter and controller and maybe other things would constantly be getting power from the battery even when you turn the ignition to OFF.
So maybe that is a problem.
But go ahead and try so we can learn something.

[Langca]

[/quote]

Ok with the number of km you can drive on one charge.

Yes, Liitokala is one of the better Chinese battery manufacturers.

But if you want to buy a battery in China to build it into a battery case for the VGA VAX, you should definitely buy one with 18650 cells that are the same size as the ones in the original battery and not one with 21700 cells that are greater mechanical. If you don't use the BMS that is in the original battery but the one in the China battery, my guess is that you will have a lot of difficulty integrating your new battery with your VGA VAX. It is not only a matter of whether the connectors mechanically fit together, but also of which electrical signals go back and forth between the battery and the scooter's electronics.

Regards, Leif.
[/quote]
Yes, that's the issue that worries me the most. I don't know if I can use the new battery directly or if I have to use the exact bms from the old battery pack. If so, I will have to find someone who is good at electricity and ask them to solder the new battery to the old bms
I don't use 18650 battery cells because if I double the capacity to 50ah, I guess the 18650 battery pack will take up a lot of space compared to the 21700 battery