powerwheels 18v conversion (works great)

[BYqSXt8Z]

Hello all!

Just wanted to show my latest project; the little one was all excited about my ebike and the family's new e-car, so I bought a used powerwheels for my child for his birthday, and it will need a battery. At first I was considering making a lithium pack, but then it needs a BMS to make sure it does not go wrong (can't expect a small child to monitor voltage and put safety ahead of fun) and cost went up quickly, then I considered using 12v power tools, but the cost was a bit too high for what it was.

My latest idea is to used my ryobi 18v battery (at it again with those!) because ryobi sells their "battery meters" which is essentially a connector for the battery pack, I already have 8 batteries and three chargers, a bunch of meters, and they have a built in BMS.

It was pretty simple, I just soldered wires onto the meter and put it in place of the SLA battery's harness, and that's it! The inside of the vehicle is so large for the pack that he can carry around extra stuff in there (on the first use I put all the batteries in there just in case, and they all fit, 8 of em!)

In the end, it works best with the 4Ah packs. The 2Ah packs only work in "first gear", the BMS stops the device when he goes in high speed for more than 50-75 feet (which is actually good sometimes). But once at the park, where he wants to go in high speed all the time, the 4Ah packs are necessary. The 2Ah pack gives a solid 40 minutes of run time.

Here is a picture of the power-meter used as a socket. I used gorilla glue to hold on some velcro and a strap so that it can hold the battery in place.

 

[Nobuo]

highly inventive mind

the cut from the BMS is maybe because the voltage sag. Is deeper as lower Ah the battery is. The Ryobi battery is lithium ion? the 2Ah one is made probably with only 1p of cells, so this is a reason there would be an appreciable sag.

Do you have a pic of all the stuff?

thanks for sharing!

 

[brooklynboy]

BYqSXt8Z, your posts helped me build my first Ryobi Battery. Maybe I can give something back.

The first is reusing the shrink wrap packaging to make a harness, the second one is a wood frame to hold/connect 6 batteries. I think for your kids power wheels, the shrink wrap would hold up fine, provided it's kept away from tiny hands. It held up just fine for 20 miles bouncing around in a battery box.

Also, my local homedepot ( brooklyn, but online is $99) has P122 for $85, which is a pack of 2 P108's 4ah. If you have an American express card, you may have a promotion for 15$ off of $75.
I think $60 is pretty good for a few fun afternoons.
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[silviasol]

Lol I have wanted to see one of these! Are you making this for your kids or is it a RC project?

 

[cal3thousand]

I hooked my kid's powerwheels up to a 6S Turnigy LiPo and it rocks! Traction is the biggest problem when you're running high voltage on these things.

 

[BYqSXt8Z]

highly inventive mind

the cut from the BMS is maybe because the voltage sag. Is deeper as lower Ah the battery is. The Ryobi battery is lithium ion? the 2Ah one is made probably with only 1p of cells, so this is a reason there would be an appreciable sag.

Do you have a pic of all the stuff?

thanks for sharing!

I'll add pictures shortly

As for the battery, that is exactly it; the 2ah is 1p and the 4ah is 2p; it is simply the BMS doing it's job just fine

 

[BYqSXt8Z]

BYqSXt8Z, your posts helped me build my first Ryobi Battery. Maybe I can give something back.

The first is reusing the shrink wrap packaging to make a harness, the second one is a wood frame to hold/connect 6 batteries. I think for your kids power wheels, the shrink wrap would hold up fine, provided it's kept away from tiny hands. It held up just fine for 20 miles bouncing around in a battery box.

Also, my local homedepot ( brooklyn, but online is $99) has P122 for $85, which is a pack of 2 P108's 4ah. If you have an American express card, you may have a promotion for 15$ off of $75.
I think $60 is pretty good for a few fun afternoons.

60$? HA! oh how I wish I could get US prices, even the regular 85$ is sweet. Canadians now have the privilege of paying 160$ for the same thing. I really need to find a way to buy stuff from the states and avoid the ridiculous shipping issues... (yes I have used reship, too pricey in the end, and boxes on the other side of the border are not that accessible for me)

I have 3 dead tools I was thinking I might cut up and use as better holders, but I am actually quite happy with my glue and velcro setup for 10$. It does become an issue when you have a p setup though, has your wood holder worked well with the batteries in parallel /avoiding that issue where the batteries go to sleep?

 

[brooklynboy]

The wood holder is great so far, but it will fly out if you hit a really hard bump. One popped out at 20 mph when i hit a bump, but they are tough and barely had a scratch. My setup is 3 in series for 54V and then parallel for 8ah, so I haven't had any issues. If you want a pdf of the template I can try to upload it here later today, just tell me # of batteries and V.

I went to school in Buffalo, NY and Toronto was like a second home. If it weren't for all the taxes you Canadians pay, I would move up there.

 

[BYqSXt8Z]

The wood holder is great so far, but it will fly out if you hit a really hard bump. One popped out at 20 mph when i hit a bump, but they are tough and barely had a scratch. My setup is 3 in series for 54V and then parallel for 8ah, so I haven't had any issues. If you want a pdf of the template I can try to upload it here later today, just tell me # of batteries and V.

I went to school in Buffalo, NY and Toronto was like a second home. If it weren't for all the taxes you Canadians pay, I would move up there.

I don't have enough of the 4AH batteries to make it worthwhile (they cost too much when I can't go to the states, which has been the case for quite a while now), and I've been working on a new tiny modular pack lately. But I am very happy to see that someone did manage to make them into useful ebike packs. If I could go back a year, I would probably go the all ryobi route (I got Headway 38120HP cells for my main pack and A123 18650 cells for my experimental pack). You should make a thread to encourage more people to do the same. It does make getting into the ebike scene that much more affordable and easier.

I do have Ryobi 40v lawn tool batteries though that I have to figure out the pinout for one of these days

 

[BYqSXt8Z]

highly inventive mind
Do you have a pic of all the stuff?
thanks for sharing!

More pics as promised!


pretty simple really­.