Series vs Parallel for sport boating

[PDR447]

As a sport boater, would you guys recommend 2 packs in series or parallel? I think I read something at some point about the pros/cons of each but I can't find it now.

The setup I'm debating:

2x 2s 5000 30c(or greater) in series for 5000mah at 4s

vs

2x 4s 2500 30c(or greater) in parallel for 5000mah at 4s

The cost of either of these setups seems about the same so that isn't a factor. Any reason to choose one setup over the other?

Thanks.

[egneg]

No - they both end up with the same specs.

[keithbradley]

Intheory, you are running more length of the same gauge power leads with the series connected batteries, and doubling the size of the wire with the paralell connection so the latter should have slightly lower final resistance.

Honestly your better option would be 2X4s 5000mah if room/weight allow it.

[PDR447]

OK, I thought I read something that said there were advantages to running one or the other even if the setup was the same but I guess not. I see the resistance thing. For racing that's probably a big deal but for sport boating I'd say that's negligible.

Why do you say 2x4s 5000? Just for the greater amp flow? 10000mah is a lot of runtime, way more than I'd ever use most likely.

[keithbradley]

OK, I thought I read something that said there were advantages to running one or the other even if the setup was the same but I guess not. I see the resistance thing. For racing that's probably a big deal but for sport boating I'd say that's negligible.

Why do you say 2x4s 5000? Just for the greater amp flow? 10000mah is a lot of runtime, way more than I'd ever use most likely.

It really depends what you are running them in, but if its a decent sized boat, the extra capacity will provide more current/give you a faster boat. More importantly though, it can add life to your esc. If you dont have the available current your setup is demanding, the result is capacitors that are trying to make up the difference. Running 2p in these situations lowers temps and reduces premature capacitor/esc failure.

[PDR447]

It really depends what you are running them in, but if its a decent sized boat, the extra capacity will provide more current/give you a faster boat. More importantly though, it can add life to your esc. If you dont have the available current your setup is demanding, the result is capacitors that are trying to make up the difference. Running 2p in these situations lowers temps and reduces premature capacitor/esc failure.

ahh, I see. All good info! thanks!

[Himalaya]

Parallel is the way to go, definitely.

*) Wires feel easy.
in a 2P config, each pack handles 1/2 current, 1/4 heat generated in wires(same wire gauge).

*) Connectors are happier.
With 2P config, each connector takes 1/2 total current and 1/4 heat generated. Smaller/lighter/cheaper connectors can be used. while with series config every connector has to handle 100% total current.

*) Packs equalized.
All packs get automatically synchronized when paralleled. When full, every pack is full; when empty, each pack has same terminal voltage, same Depth of Discharge. This will prolong battery lives. In contrarory Serial connected packs suffer from one pack gets empty sooner than the other, this pack is in very high risk to be overdischarged. Packs never have same capacity, so this always happens. While in parallel even a 5000mAh pack + a 500mAh pack cause no problem.

*) Easier recharge.
More and more parallel charge adapters on the market, very few if any series adapter is available, the experts at charger companies know the reason, so do you.

*) less wiring job. Easy to work with, just red wire to red wire, black to black, no complex polarities to care about.

[SweetAccord]

Parallel is the way to go, definitely.

*) Wires feel easy.
in a 2P config, each pack handles 1/2 current, 1/4 heat generated in wires(same wire gauge).

*) Connectors are happier.
With 2P config, each connector takes 1/2 total current and 1/4 heat generated. Smaller/lighter/cheaper connectors can be used. while with series config every connector has to handle 100% total current.

*) Packs equalized.
All packs get automatically synchronized when paralleled. When full, every pack is full; when empty, each pack has same terminal voltage, same Depth of Discharge. This will prolong battery lives. In contrarory Serial connected packs suffer from one pack gets empty sooner than the other, this pack is in very high risk to be overdischarged. Packs never have same capacity, so this always happens. While in parallel even a 5000mAh pack + a 500mAh pack cause no problem.

*) Easier recharge.
More and more parallel charge adapters on the market, very few if any series adapter is available, the experts at charger companies know the reason, so do you.

*) less wiring job. Easy to work with, just red wire to red wire, black to black, no complex polarities to care about.

Exactly!