# Are LiPo batteries more suitable for 1st stage electric power than Li-ion batteries?

I've just ran across two mentions in Scott Manley's videos of LiPo batteries (Lithium-polymer) in first stage launch applications. These involve power levels of megawatts.

Many/most large terrestrial transportation applications that I've heard of use lithium ion batteries, often made up of a collection of 18650 cells.

Are LiPo batteries more suitable for 1st stage rockets than Li-ion batteries? If so, why?

• slightly related and currently unanswered: Are the ejected first stage Electron rocket batteries really incinerated? – uhoh May 6 at 5:36
• The thing we care about is the discharge rate. It is usually given in C a discharge rate of 1 C means we release the stored energy in 1 hour. A lower stage might burn say 2.5 min which means we need a discharge rate of 24 C if we want to completly discharge our batteries which is high but managable for LiPo commonly used in e.g. fpv drones and rc cars (they go up to ~75 and are marketed up to a constant 100). I have no idea about Li-ion batteries therefore just a comment. The internal resistance is the limiting problem here. – Christoph May 6 at 6:43
• @Christoph I see, since mass is such a critical factor in launch vehicles, when comparing two batteries I wonder if the one with higher [specific power]() is really more important than the one with higher C? – uhoh May 6 at 6:50
• Yeah the interesting thing for us is the usable specific energy which is basically min(specific power * burn time, specific energy). But if you throw away your batteries like the electron does you basically only care for specific power so that you can throw away a battery pack as often as possible. You don't want to take the batteries all the way to space with you. – Christoph May 6 at 7:00
• @Christoph it sounds like you are in a good position to post an answer :-) – uhoh May 6 at 7:02