Short range battery ideas

I have a mid drive kit installed on a fat tire bike, the stats on the motor are: Multiwatt (650~1680W), with controller:48V continuous 840~1680W, 40A continuous, Max 100A, and am working on getting the battery set up to meet my needs and am looking for recommendations.

The vast majority of the time I think I will need to travel under 1 mile, and do have some big hills to climb. I would never be going over 5 miles for sure. I am looking at 3-5ah hobby king packs, but wanted to ask to make sure I am getting what will meet my needs. I would like to try 36v first to see if its enough to climb the hills, if not them Ill bump it up to 48V. Whats the most economical, simple set up for my needs?

Thanks

Because you want to carry a small pack, you need better c rate packs. And bear in mind, your battery will heat up and wear out fast, if you pull 10c from a 20c pack. Ideally you will want to use at least 30-40c stuff to pull 40 amps from a 5 ah size. The goal is that the pack does not get very hot when you use it.

Your controller is a monster, so you need some monster c rate cells. You might not see 100 amps for very long, but I'd say you want at least 40c pack, so you can pull 10c from it and keep it's cool.

10c x 5 ah, 50 amps. That should do er. Get two 5s packs for 36v, then if you want to go 48v you can add 4s more.

Also to add to what Dogman is saying, reading through past posts about Hobbyking Lipo packs, what he and many others who have experience with hobby lipo's say is that , it is best to only use continuously , 25%-35% of their C Rating ,
25% being better for the battery .
( I am writing this to also remind myself before ordering batteries )

That is why in his last sentence he is saying that if you want to pull 50 amps from them then get ones rated at 30c or 40c .

Multistar's only have a 10c or lower rating, so they are more suitable to the smaller/lower watt motors.

Also many Lipo's on Hobbyking are 6s , so with two of them to make 12s you could , with the right charger, have a bike that runs between 36 and 48 volts.

Another option is to use larger amperage packs, since you would only be using two anyway.

dogman dan said:

Because you want to carry a small pack, you need better c rate packs. And bear in mind, your battery will heat up and wear out fast, if you pull 10c from a 20c pack. Ideally you will want to use at least 30-40c stuff to pull 40 amps from a 5 ah size. The goal is that the pack does not get very hot when you use it.

Your controller is a monster, so you need some monster c rate cells. You might not see 100 amps for very long, but I'd say you want at least 40c pack, so you can pull 10c from it and keep it's cool.

10c x 5 ah, 50 amps. That should do er. Get two 5s packs for 36v, then if you want to go 48v you can add 4s more.

Click to expand...

Most 48V controllers have an LVC of ~42V, so a 36V battery pack won't even turn it on. You Need 12s minimum (44.4V nominal). It may be cheaper to run a 10ah 20C pack than a 5ah 40C pack, Both will have the same amp rating (100A).

If you can set your LVC on your controller getting (2) HK MultiStar 6S/12A packs might work well for you. I have a MP5 and can program the controller via BT on the fly (when BT connects which is another story!). Otherwise, you can get a 10S pack by combining a 6S and 4S pack with the same capacity ~ 10 to 12A. Even if you only use 2-3A/hrs, it would be good to use a higher capacity pack for better sustained C rates during sustained discharge events and many more duty cycles since you can charge them up to 4V per cell.

Now, you can still get away with using 5A Zippy packs, but the MultiStars are almost comparable in size with more than double the capacity--well worth it!

Uh, you don't even seem to know the diff between amps and amp hours bro.

If those multistars are 10c, then youd only have 50 amps at full 10c rate,from a 5 ah size pack. And his controller will allow a spike of 100 amps.

Then cut that c rate to what will really work, and not result in a hot pack, and you are now limited to 12.5 amps of power. 10c won't be strong enough to use with that controller, if the pack size is only 5 amps.

He needs 40c,50c, that ballpark.