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my problem with that is that 2 packs only give me 5ah which would be less than 10mion of ride time. I get 15min with my 7ah TOPs right now. $50 in lead or $400 in lipo,

Ohms low states: The total current is equal to the sum of the individual branch currents.

Therefore if the battery is 5000mA each, 2 in parallel would be 2X5000mA, which is 10A. The total cost of the batteries is $200.00 for 4 batteries. These will also function like a 12 A/h pb battery.

I get 15min with my 7ah TOPs right now.

15 min on 7 A/h? I think you better check your batteries.

$50 in lead or $400 in lipo, they are more powerful, but they will drain quicker...then you run a risk of over draining them, which is less of a problem for lipo than lead. You can drain lipos more than lead, you can charge lead more than lipo.

$100 in lipo, not $400. They will not drain quicker. They have a denser energy and more capactiy the lead acid. Draining Lipo is MORE dangerous then draining Pb batteries. Pb can be dropped to 80% Capacity. Lipo's should never get under 85%.

If 1 lipo cell is out of balance...FIRE even with bms boards charging is not full proof.

If one lipo cell is out of balance it will not cause a fire unless its voltage goes under 85% or 3V per cell. When you charge you need a balance charger. they cost about 20 bucks new for a 5-6A version and they will charge every type of battery including PB.

I wish I wasn't so sketched out by lipo. I have a couple plane and choppers, 1 of my 11.1v got super puffy after I used it to power some led lights on my bike. made me mad!

You dropped the cells below 3V plain and simple. Lucky you did have them explode or catch fire. Most lipo's will just "puff" when there undervolted. Keep them above 3V per cell, 3.2 is better for battery life.

I am interested in kelly! I was thinking of going to 3 big amp hour batts with a 100a kelly.

Check your batteries. I have 3 17 A/h batts in my sons bike before the lipo's. The kelly controller is affordable and has over-current and most importantly programmable low voltage shutoff.

currently I'm running 48v 7ah on a 36v 650watt motor. thinking of running 3 18ah on the motor.

Good luck fitting 4 of them in there. With 3 17 A/h batteries I was able to run for about 30-40 minutes on a 750W PM DC motor.

I think the more powerful controller would open the motor up without over heating. I can get a 100a 36v kelly for $60


More amps, more heat, the motor will get hotter. The controller will protect it. I have a device that restrict current of temperature gets too high. Go with the 24-48V version. it opens the doors for future upgrades.

.Thinking even just 3 14ah. Gotta stick with lead for now. 1 14ah high rate batt is like $36! not bad at all.

I use 10AWG on anything below 100A. Remember gauge becomes less of a factor because we have suck a short length of wire. The reason for going larger diameter wire is to reduce resistance. In any case, bigger is better in regards to wire.

Could you send me some links for installed kelly pics? would like to see the wire connectors. I usually use 12ga wire. I don't want to go with 8ga, but I feel it's time for 10gauge.



This is the controller I am using on my sons little Razor scooter I am building. Schematic is on page 10/17. Displaying picture would really be useless because you cannot see all the connections.

http://kellycontroller.com/mot/downloads/KellyKDUserManual.pdf
 
I actually may have some D cell nicads available. they are 5cell pks 6v 5ah 1.5lb each. 16 will give me 48v 10ah bring the weight of the batteries down by 13lb...right now the bike is 110lbs or so. Seems like a win since I can run them down further than lead. Feel stupid but I'll have to figure out how to hook them up to run and then charge. also need to find a decent charger for all those batteries. we're looking at 80cells or more. I'm not electrical engineer I'm just a line cook that likes to run the trail in my down time.
For a 48 volt pack 10 ah with those, yea 80 cells would be right, so you would have to make two 48 volt packs and wire them in parallel to get the 10 ah out of them. Any info on the cells used in the packs though, you'll want to make sure they are high discharge rate obviously. Charging wouldn't be a big problem, just need a 48 volt nicad charger, which a few places sell online for, i think 40 dollars or so.
 
Just get a different controller, and as an option lipo batteries. I am using a 24-28V Kelly controller and two 6S1P 5000mah Lipo's (22.2v per batter) in my son's mini-moto. You will decrease the amount of milage you will be able to travel but the hill will become much easier with 100 amps.

$100 shipped - Kelly Contorller KDS48100A

$45 each plus shipping - ZIPPY Flightmax 5000mAh 6S1P 25C
Wow. Now you've made me want to check out lipo! Of course I'm a throttle junkie so I'll probably end up in a ball fire in a ditch.
The zippy's are super cheap when you put it in that perspective. $200 is what it costs for 4 sla 14ah...if for zippys can match it than why not?!
I got 12 7.2ah batteries for $30 so I've been running my bikes on those. I have an MX500 running on 8, a MX650 running on 4, and another MX650 running on 4 old 12ah batteries.
The 650 gets less than 1.5mph range @ 20.3mph not very good.
The bikes are also 105lb + my 160lb self.
So what about the turnigy vs the zippys they are double price...does that give any low volt leeway. I usualy end up crawling in the yard from the trail. Maybe that's why my batteries suck. What's the fun if you can't push your limits? I also charge on 8a w/ the 48v packs through a schumaker car charger.

1 of my bikes desperately needs batteries. I'm going to try and use a desulphator on the 12ah batts, they can get 3mi range.
I'm glad you spelled the lipo picture out for me. I feel a little more confidant about them. I have a dual motor standup scooter than needs 48v to run.
what kind of run times can you get out of lipos. they sound like they can't be discharged anymore than slas...slas just damage themselves, lipos damage you. With a lvc buzzer or other things it's preventable.
The kelley seems like the route to go. I have a yi yun 100a controller right now. it throws too much heat to my 1000watt, 650,and 500 on 60, 48, and even 36v.
 
For a 48 volt pack 10 ah with those, yea 80 cells would be right, so you would have to make two 48 volt packs and wire them in parallel to get the 10 ah out of them. Any info on the cells used in the packs though, you'll want to make sure they are high discharge rate obviously. Charging wouldn't be a big problem, just need a 48 volt nicad charger, which a few places sell online for, i think 40 dollars or so.

Excellent! I'm getting hooked up soon so hopefully I'll be able to do something while the weather is tolerable. Wasn't too cold out today so i ran the dog 2x's around 1.5mi each trip and only about 8min-10min at a time.
 
So the cells are about as much as 4 14ah slas, that's 4 lipos, I'd prefer 8, but that still only gives me 15ah, but the weight and cycle life are a good reason to spend $400. HK also sells a decent 5a lipo charger for $40 Just as cheap as my car charger. My eventual goal is more than 100a...I want a torquer that will pull a wheelie from a standstill. I can't get the preformance from lead without a lot of lead, but it's half as cheap. so if I get 3years out of it that's cool. Still haven't found a way to keep my motor cool right now. I ran the bike hard in the snow, that was only 30a but it's weather proof. I have a fan for my motor now, but I can't run the snow with it.
Whole other issue. Right now I've been lucky enough to ride on super cheap batteries. Haven't had to put up a lot of cash yet. My dirtbikes were 2nd hand...$200 for all 3. 2 had worthless batteries. the 7ah fit under the cover and that's good enough for me now...3 bikes they can't all be lipo! I also have 2 razor scooters 1 a dualie and the other has a 1000watt motor.

I want to focus on making one dirtbike scream, but still run the others for my kid and the neighborhood gang.
 
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