connecting a 65c in serie with 75c rate

[MrUnlimited]

Is it possible to connect a 65c 4s 6000mah lipo with a 75c 4s 6000mah lipo in serie?
yes or no? I have 3 lipo of this type: https://www.ebay.com/itm/Turnigy-Gra...vPKi:rk:2:pf:0 But they are replaced with this one: https://hobbyking.com/de_de/turnigy-...ck-w-xt90.html
I need 4 packs in my cat so that's why.

[Doug Smock]

Ideally you'd want to run packs of the same age, capacity, C rating, & #of cycles.
My guess is you'll be fine unless the used pack has a huge # of cycles on it or has been mistreated. You'll know after the first discharge / charge cycle what you have in the pair.

[Speedfreek]

Is it possible to connect a 65c 4s 6000mah lipo with a 75c 4s 6000mah lipo in serie?
yes or no? I have 3 lipo of this type: https://www.ebay.com/itm/Turnigy-Gra...vPKi:rk:2:pf:0 But they are replaced with this one: https://hobbyking.com/de_de/turnigy-...ck-w-xt90.html
I need 4 packs in my cat so that's why.

I was always told you are risking a lipo fire mixing C rating batterys Expecially different brands....