72V 100A 60Ah 4.3kWh 10s24p 200lbs.....

Mike B said:
A 40 amp continuous discharge rating would be what I would expect to see from a 40 AH battery. A 1C rating.

With 2C (80 amp) momentary. That should be fine.

A 12 amp (.3C) rating means a limp battery.
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That CALB battery is just useless to me Mike B. It's just not enough for me. :-||:-||
 
You are looking at a big motor, 5 KW.

A 15 AH, 48 volt battery is a good fit for a 1 KW motor. That's 750 watt-hours.

If you scale it up from there, a 5 KW motor would need 3.8 KW-hours.

A 72 volt 40 AH battery would have 3 KW-hours, so you are not so far away.

I think you need 96 volts (2 x 48) at 40 AH. That would be 4 KW-hours.
 
Mike B said:
You are looking at a big motor, 5 KW.

A 15 AH, 48 volt battery is a good fit for a 1 KW motor. That's 750 watt-hours.

If you scale it up from there, a 5 KW motor would need 3.8 KW-hours.

A 72 volt 40 AH battery would have 3 KW-hours, so you are not so far away.

I think you need 96 volts (2 x 48) at 40 AH. That would be 4 KW-hours.
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You are correct. I could go that route.

I simply do not see anything that can remotely match this batteries specs here though. As dangerous as it is, it simply performs like a bat out of h3ll. It's a line I'll just have to walk. LOL

https://www.hobbyking.com/hobbyking/store/__24297__Turnigy_nano_tech_A_SPEC_4000mah_10S_65_130C_Lipo_Pack.html

24297.jpg
 
You are thinking of 20 of those batteries with 2 series connection, of 10 each in parallel?

Yeah, that will give you 74 volts at 40 AH, 3 KW-hours.

Lipo's don't scare me that much, they are only dangerous if overcharged. If you have a good charger that's not trying to quick charge them and has automatic shut off, all should be well.
 
Whoever took this picture of a Cycle Analyst (on a modified Stealth Bomber) was using a R/C LiPo battery of the type shown above, if not the exact same battery that I just posted above. That battery will give me at least 247A, as I see no soot or scorch marks on that Cycle Analyst. It appears to be fine. laff

Fighter-peak-stats.jpg
 
Mike B said:
You are thinking of 20 of those batteries with 2 series connection, of 10 each in parallel?

Yeah, that will give you 74 volts at 40 AH, 3 KW-hours.

Lipo's don't scare me that much, they are only dangerous if overcharged. If you have a good charger that's not trying to quick charge them and has automatic shut off, all should be well.
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You are correct. That's the road I'm headed down. I simply don't see any other good alternative. I'm a newb to LiPo batteries but I learn quick. I'll just mount a fire extinguisher to my bike if I have to. LOL
 
You're gonna need some stout batteries to provide 100A in a compact 72V configuration, either 6 AGM batteries or take your chances with Lipo, either that or maybe two of the strongest 50A rated 72V LiFePO4 bike battery packs run in parallel for 100A total. It's either heavy or risky or expensive, take your pick of poison. 12V 20Ah AGM batteries weigh about 20-25 lbs each, so a 72V pack would be quite the lead anchor, which causes the motor to pull more amps and run them down faster than lighter batteries, the RC Lipo can really rip, but it needs to be set up correctly and the cells charge balanced, discharged properly, and monitored carefully. The big LiFePO4 packs are the best balance between weight, maintenance, ease of charging, and reliability, but they are also astronomically expensive.
 
Batteries are typically cheapest off Ebay, you could run these 72v in a quad parallel connection and deliver 80A, but they're only 10Ah, so he fun will be up in about 15-30 minutes of riding. All for the small sum of $2920, compared to a 12v 6 pack of SLA's for about $120 with similar output specs, disregarding weight, makes lead seem like a good deal. That's why I run lead, it's cheap and offers performance if you don't need big Ah specs for long ride times.
 
Lead acid batteries suck. What are you a cave man?

Lithium batteries are what make ebikes work. And ecars and eeverything.

Go lithium or go home.
 
Yeah Baby!

That will be a serious battery. Only 61 lbs too.

My 48V, 20 AH, LiFePO4 weighs 25 lbs.
 
Mike B said:
Yeah Baby!

That will be a serious battery. Only 61 lbs too.

My 48V, 20 AH, LiFePO4 weighs 25 lbs.
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That will bring my bike to just under 190 lbs......not including the motor. LOL

Rated Continuous Power of my motor is 7.5kW so the 220A the batteries can deliver will never get continuously used at that level. Oh well. I'll get over it.
 
Lead acid batteries suck. What are you a cave man?
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No, I just won't waste hard-earned money being an early adapter guinea pig.

$100 worth of AGM batteries only weighing 40 lbs powers my 60V, 6000W electric motard nicely.

attachment.php


Most rational people would call spending nearly $3k on Chinese batteries for a bicycle a rather caveman thought process, or lack of rationality.

The bike weighs 125 lbs and delivers a good 15-25 minute thrill ride, and the torque is a great workout.
 
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Mike B said:
You have seen Mike's bike yes?

His wheels are bigger than your motard.
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Yeah my 4.125" tires are huge and heavy for sure, but you can only really feel it if you try to lift the bike off the ground.

DSCF3027.JPG


I also have to switch back to my original Motenergy motor choice to be able to use that 275A for 10 seconds the batteries can deliver. The other Golden Motor will burst into flames if I tried that. I just can't have that. LOL

http://electricmotorsport.com/ev-parts/motors/brushless-motors/pmac-ss-me0201014201-pmac-motor-24-72v-6-hp-cont-19-hp-pk.html
 
16v4nrbrgr said:
No, I just won't waste hard-earned money being an early adapter guinea pig.

$100 worth of AGM batteries only weighing 40 lbs powers my 60V, 6000W electric motard nicely.

attachment.php


Most rational people would call spending nearly $3k on Chinese batteries for a bicycle a rather caveman thought process, or lack of rationality.

The bike weighs 125 lbs and delivers a good 15-25 minute thrill ride, and the torque is a great workout.
Click to expand...

You failed to mention the Amp Hours that your batteries deliver. My 55Ah is a lot of hours. A whole lot of hours at 110A (continuous). My spinal cord will wear out before my batteries do. laff
 
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