I’m deciding between using lipo and li-ion for my new board… according to the numbers, lipo has 5x the volumetric energy density but li-ion has 1.5x the gravametric energy density…does that sound right you you guys?
I would suggest using the search function as this topic has been beaten to death here a thousand times. Which will likely happen again right below my post.
There’s loads of info out already.
5x or 1.5x what? lipo are much less energy dense than ion but you need a level of power too and you cant just get the most energy dense cells as they’re only good for maybe a couple of amps power.
It sounds like you are already analysing the problem in the right way. For us to help you make a decision you also need to explain your
- range requirement
- power requirement
- assembly ability
In general, Lipo are
- large (for the capacity, as you point out in your post)
- easy to assemble into skate packs as you don’t need to weld them together.
In general 18650 Li-ion are
- more expensive per Wh and per W
- better energy density (weight and volume)
- lower power density
- highly configurable. Any combination of 10s4p, 12s5p, 8s10p etc.(but requires welding)
I’m making a dropdeck longboard that pulls 40A continuous and 130A burst (based on motors) and I’m hoping for about 400Wh. I’m debating between…
- a custom 12s2p 10Ah 12/24C Turnigy lipo pack
- a 12s4p 12Ah Samsung 30Q li-ion pack
I want to make the packs in 4 parts (2s2p unit on the board) because I can only charge a 6s at a time and I want to make the extra parallel cells optional for less weight and lower speed when I’m on campus.
That’s a little ridiculous, if you want to go slower buy a BT module and configure speed modes
I’m not gonna pull out the batteries to go slow, I’m just going to have less amps available so I’ll get less acceleration and save a kilo of battery weight, since I don’t have much space to accelerate on a campus it will effectively be slower since I’ll never get to top speed…but I’m not sure if there is a way to not blow the batteries by having the ESC set to the higher amp limit
get a 12s4p from this guy, he knows how to build a pack
Those lipo are unlikely to really have that c rating or discharge rating and likely half what’s stated.
Lipo are easy though
Until you make a mistake, right hummie?
Well lipo are pretty easy not to make a mistake! But do need protecting. Maybe that’s my constant mistake ur alluding to.
hmmmmmmmmmmmmmmmmmmmmmmmmmmmmm. youve got me thinking
I’ve nearly burned my house down with a 2s lipo so maybe I should stay away from Lipos…the scortch marks on my carpet attest to my incompetence
How did u?
Long story short I was making an analog robot and I crossed the leads…the wires melted into the carpet
your somewhat lucky the leads didnt weld together for a few seconds.
That spot is in my doorway so I walk over it dozens of times a day for years now, this is way more difficult to make than any electric skateboard BTW
It’s a common misconception that LiPo are more dangerous than li-ion. They are both dangerous. LiPo are easier to use and thus used by people who don’t know what they are doing more often and thus more accidents happen with LiPos. That doesn’t yet make them more dangerous.
I used to think that for a long time, but it is easier to puncture a lipo than a li-ion so its still kinda true
Well, lipos are designed to be placed into a hard shell. Using them without one is, IMO, foolish.
See the graphene lipo series. They’ve all got a hard shell around them, I’d say they’re pretty safe.