Noob's Battery Price Comparison Summary For Noobs

[julesa]

Also, if you need a higher c rating, the bosch 36v drill kits are selling for <$200 shipped on ebay with a charger and 2 fat pack battteries.

I really need capacity more than I need high current. I'd be getting at least 15Ah no matter what. I just have a couple long, steep hills I need to climb (12% grade at one point), that's all I'm really concerned about -- don't want the pack to cut out on me. My controller's limit's set around 25 amps but depending on performance on those hills I might want to tweak that upward. I'm planning to pedal up the hills, and I'm in decent shape, I just don't want to be all rubber-legged and sweaty at the top. Maybe the Ping would be a good fit.

Remember, I'm the Noob in "Noob's Battery Price Comparison Summary For Noobs"

 

[Tom]

What kind of controller do plan to use? I could be wrong but I think a 48v/25 amp controller will only pull 25 amps at 48v, so you should be fine with a 20ah battery. If you want more power I think you would need to go with another controller or feed it more volts. Also, keep in mind battery technology will evolve, so I wouldn't pay a premium today for a long lifespan since it will likely be outdated before you realize the lifespan.

 

[julesa]

What kind of controller do plan to use? I could be wrong but I think a 48v/25 amp controller will only pull 25 amps at 48v, so you should be fine with a 20ah battery. If you want more power I think you would need to go with another controller or feed it more volts. Also, keep in mind battery technology will evolve, so I wouldn't pay a big premium today for a long lifespan.

My understanding is that a 25 amp controller will limit continuous current to 25 amps but if you accelerate hard or hit a steep hill, peak draw can go well above the controller's rating... but I could be wrong.

 

[Tom]

Quite possible. I am just getting into this as well so not an expert by any means either. :wink:

 

[pwbset]

My understanding is that a 25 amp controller will limit continuous current to 25 amps but if you accelerate hard or hit a steep hill, peak draw can go well above the controller's rating... but I could be wrong.

A pedal first Clyte 20a controller will see spikes into the upper 30s/low 40s briefly. Since I soldered my shunt I'm seeing spikes up around 60a, but it's rare... like from ~5mph starting speed full throttle on a really steep hill and the controller rattles so loudly it's easy to go oops and back off again. Even with a soldered shunt I can't maintain more than upper 30s to around 40a, but that's very likely because my battery pack won't deliver any more than that without sputtering like mad as their BMS trips.

 

[julesa]

A pedal first Clyte 20a controller will see spikes into the upper 30s/low 40s briefly. Since I soldered my shunt I'm seeing spikes up around 60a, but it's rare... like from ~5mph starting speed full throttle on a really steep hill and the controller rattles so loudly it's easy to go oops and back off again. Even with a soldered shunt I can't maintain more than upper 30s to around 40a, but that's very likely because my battery pack won't deliver any more than that without sputtering like mad as their BMS trips.

Thanks, pwbset. Sounds about like what I've read from others here... a Ping 48v 20Ah (with a 60A BMS cutoff) should be OK for my setup, if I am happy with the hill performance of the unmodified controller. But I won't know that until after I buy a battery... I think it will be worth paying a little extra money to be 100% sure I'll be happy with my battery investment. THANKS GUYS!