Greetings
I have 2 Evolve electric skateboards. One is the Carbon 2nd Generation with the single motor and 10Ah battery and the other is the Bamboo 2nd Generation with single motor and 7Ah battery.
I use it to commute every now and then (whenever I wake up with a pair big enough since Ive been seeing a lot of police on the road I would ride on and you don't want to catch a german police officer on a bad day as he will take the board away)
and I cant make it to where I want to go and back going full speed. I get to my destination but on the way back, usually 1/3 the way the board doesn't let me go into the fast mode anymore, so im limited to 15Kmh (annoying when its usually 30-33Kmh. I run the all terrain tires as part of the way is a dirt track. All terrain tires lead to higher energy use. Its an 14.5km stretch, so after like 9-10 the voltage sag is too much it limits to low power mode.
Anyway, I want to build a new internal battery for the Carbon. I have plently of NCR18650PD's. In a 10s6p config this would give me 17.4Ah. Significantly more.
There is some guy on endlesssphere who has done exactly this but with NCR18650B's and got 20.4Ah. Ill be copying his build for this.
For the Bamboo though I had a different plan. More then two weeks ago I was looking into this all ready and a new internal battery doesnt really fit. A 10s4p could maybe just fit if I really push it but I cant just place the battery case of the bamboo 3mm lower to allow for enough room and I would be squishing the BMS in there. Not going to risk it.I thought Id leave this one out and go for an external Range Extender pack.
Ordered a spot welder last week and over the weekend and a couple hours this week I built and refined my pack.
So my plan was that I can have a pack in my backpack and run a cable down to the board. First I thought I could use a switch of some sort so I can plug in the pack, flip the switch and use the external one. Clean and simple.
Ordered some switches but came to the conclusion that it wont work with those so I abandoned that and just went with plugging out the internal and plugging in the external pack. Ill post later today about those switches, maybe I just wasnt thinking straight and of you guys can figure it out ;D
I extended the cables from the internal pack and the cable going to the controller. They are just T plugs so that was easy. The two cables are now going out the back of the board. To find out what current the motor uses I plugged a Watts Up meter (also with T plugs) in between and it ended up being a whopping 24A! and a constant load of about 12-15A to hold a speed of about 28Kmh. (it is a 350w motor after all)
Then I thought of safety and practicallity. Plugging in the external pack with a T connector is kind of dangerous if I fall of the board or jump of and it doesn't come loose so a magnetic plug would be the way to go, also makes plugging it in easier.
I have these magnetic Rosenberger plugs from ebikes which are perfect.
Soldered up a male plug with a female T plug to place on the board permanently (into the little hole being the axle mount. This would be the bit I just plug into the controller/motorcable.
Then I would place a female T plug on the battery and build a roughly 1.4m long cable with male T plug and female Rosenberger plug to connect down to the board.
Now to the pack
Its a 10s4p from the NCR18650PD cells. Ordered a BMS from ebay, 10s 35A. I double and trippled up the nickel strip where needed and soldered on the end wires onto all 4 of the last cells to spreadout the current on the nickel. To attach the two 5s banks with one another I used 2thick wires.
At first I wired it all up and the BMS got warm, didn't think much of it as I thought it was just balancing the cells. Next morning it was still warm so I took it apart and noticed 1 pack of cells went down to 3.84V. I checked all the wires again and it turned out I mixed up two wires.
Used my iMax to charge up the low blockand the blockin front and behind it since they were at 4.05V for some reason.
Since then the BMS doesn't get warm and seems to be doing its job.
To charge the pack I have a male Rosenberger plug on the side as I have a charger with that end all ready.
Placed a s*** load of duct table and some foamin between the two 5s banks and did the same on the outside of the pack. I might order some huge heatshrink for the outside as well to make it look more professional : the duct tape doesn't give the best image of safety sadly.
Ran a discharge test on it using a West Mountain Radio and a 36V 8A load. The Load slowly tapers down to about 6.5A while the voltage drops. It ended up discharging 11 Ah. So now I have abut 17.5Ah of usable capacity for my Bamboo at an extra 2.5kg that I have in my backpack.
Ill post more pics later but im pleased to say that IT WORKS PERFECTLY!!!
Any feedback is appreciated of course : especially regarding safety.
I have 2 Evolve electric skateboards. One is the Carbon 2nd Generation with the single motor and 10Ah battery and the other is the Bamboo 2nd Generation with single motor and 7Ah battery.
I use it to commute every now and then (whenever I wake up with a pair big enough since Ive been seeing a lot of police on the road I would ride on and you don't want to catch a german police officer on a bad day as he will take the board away)
and I cant make it to where I want to go and back going full speed. I get to my destination but on the way back, usually 1/3 the way the board doesn't let me go into the fast mode anymore, so im limited to 15Kmh (annoying when its usually 30-33Kmh. I run the all terrain tires as part of the way is a dirt track. All terrain tires lead to higher energy use. Its an 14.5km stretch, so after like 9-10 the voltage sag is too much it limits to low power mode.
Anyway, I want to build a new internal battery for the Carbon. I have plently of NCR18650PD's. In a 10s6p config this would give me 17.4Ah. Significantly more.
There is some guy on endlesssphere who has done exactly this but with NCR18650B's and got 20.4Ah. Ill be copying his build for this.
For the Bamboo though I had a different plan. More then two weeks ago I was looking into this all ready and a new internal battery doesnt really fit. A 10s4p could maybe just fit if I really push it but I cant just place the battery case of the bamboo 3mm lower to allow for enough room and I would be squishing the BMS in there. Not going to risk it.I thought Id leave this one out and go for an external Range Extender pack.
Ordered a spot welder last week and over the weekend and a couple hours this week I built and refined my pack.
So my plan was that I can have a pack in my backpack and run a cable down to the board. First I thought I could use a switch of some sort so I can plug in the pack, flip the switch and use the external one. Clean and simple.
Ordered some switches but came to the conclusion that it wont work with those so I abandoned that and just went with plugging out the internal and plugging in the external pack. Ill post later today about those switches, maybe I just wasnt thinking straight and of you guys can figure it out ;D
I extended the cables from the internal pack and the cable going to the controller. They are just T plugs so that was easy. The two cables are now going out the back of the board. To find out what current the motor uses I plugged a Watts Up meter (also with T plugs) in between and it ended up being a whopping 24A! and a constant load of about 12-15A to hold a speed of about 28Kmh. (it is a 350w motor after all)
Then I thought of safety and practicallity. Plugging in the external pack with a T connector is kind of dangerous if I fall of the board or jump of and it doesn't come loose so a magnetic plug would be the way to go, also makes plugging it in easier.
I have these magnetic Rosenberger plugs from ebikes which are perfect.
Soldered up a male plug with a female T plug to place on the board permanently (into the little hole being the axle mount. This would be the bit I just plug into the controller/motorcable.
Then I would place a female T plug on the battery and build a roughly 1.4m long cable with male T plug and female Rosenberger plug to connect down to the board.
Now to the pack
Its a 10s4p from the NCR18650PD cells. Ordered a BMS from ebay, 10s 35A. I double and trippled up the nickel strip where needed and soldered on the end wires onto all 4 of the last cells to spreadout the current on the nickel. To attach the two 5s banks with one another I used 2thick wires.
At first I wired it all up and the BMS got warm, didn't think much of it as I thought it was just balancing the cells. Next morning it was still warm so I took it apart and noticed 1 pack of cells went down to 3.84V. I checked all the wires again and it turned out I mixed up two wires.
Used my iMax to charge up the low blockand the blockin front and behind it since they were at 4.05V for some reason.
Since then the BMS doesn't get warm and seems to be doing its job.
To charge the pack I have a male Rosenberger plug on the side as I have a charger with that end all ready.
Placed a s*** load of duct table and some foamin between the two 5s banks and did the same on the outside of the pack. I might order some huge heatshrink for the outside as well to make it look more professional : the duct tape doesn't give the best image of safety sadly.
Ran a discharge test on it using a West Mountain Radio and a 36V 8A load. The Load slowly tapers down to about 6.5A while the voltage drops. It ended up discharging 11 Ah. So now I have abut 17.5Ah of usable capacity for my Bamboo at an extra 2.5kg that I have in my backpack.
Ill post more pics later but im pleased to say that IT WORKS PERFECTLY!!!
Any feedback is appreciated of course : especially regarding safety.