Parallel Battery connection advice

[Snowride]

I want to use 3s batteries in parallel to achieve a 6s pack. Question is, can I mix different mah 3s pacs such as 1 a 6000mah and a 3000mah of the same brand and both being 3s to achieve 4000mah? pack@ 6S?

Reason I ask is I have a bunch of 3s 6000mah batteries and I am worried about getting a little too heavy plus the virtual size if I combine 2 of these to form a 6s 6000mah. I can lessen this by going with my 6000mah pack and purchasing a few 3000mah packs which are quite cheap in comparison and connecting them up with my 6000mah packs.

Final for not simply going with a single 6s massive battery such as a single 6S 8000mah is we all know a single cell can go bad on any pack and if this happens on a single 6s, the $150++ pack is basically scrap. I prefer to use 2 smaller 3s packs and loose only an inexpensive smaller 3s if a cell were to die. Price wise it is similar. Make sense?

[egneg]

You are hooking them up in series to make two 3S into one 6S pack. They need to be equal or you will have

[Make-a-Wake]

Two 3s batts in parallel make 3s firstly, secondly i would never mix batteries of cells, different mah and C rating. Only time i know of that would be safe is a 2s 5000 40c connected in series to a 3s 5000 40c for 5s.

[Snowride]

Thanks for the replies. I know how to hook them up but for some reason I keep mixing up the series/parallel wording. Just can't seem to get it stuck in my head.

So basically if I hook up 2 of my 3S 6000mah packs in series they will form a single 6S 6000mah pack. If I do this, I will run 2 of these in parallel to end up with supplying 6S 1200mah in my apparition running on a 1300kv. I just weighed to 3s pack and combined they total up to 2 1/4 lbs/1000gr so the combined final weight of batteries in the boat would be around 4 1/2 lbs/2kg. Is this too much for this boat to handle? Option B is to simply run 2x 3S packs (one per side) in series and have shorter run times. Best scenario?

[siberianhusky]

What kind of setup that you need that much capacity?
Gotta watch out for heat soak with extended run times. Things might be fine for a 4 minute run but an 8 minute run might end not so good. As the motor mount, entire motor, cooling jacket and everything heats up it might not be able to keep things cool enough.
You are adding a lot of weight which in turn will make everything have to work much harder to push the boat at the same speed.
Be careful for the first few runs if you give it a go.

[Snowride]

This will be in an apparition 800mm with T180esc and 1300kv single motor. Looking for long run times but keeping things reliable. Suggestions on mah 6S total best setup please.