Switchable Series/Parallel Battery Setup

[laxplayer9009]

I'm wondering how to go about a switchable series/parallel battery setup? I'm going to have (2) batteries and it'd be nice to be able to switch them between series and parallel. If its even possible assuming relatively even discharge between the 2 regardless of configuration (series/parallel).

I believe someone on here has already accomplished this using a 3-way switch ON(series)-OFF-ON(parallel). But i'm not sure how to actually power the board in that case, and ensure no spark on powering it on.

No small switches are capable of 80+Amps. Maybe some kind of MOFSET or SCR?

It'd be awesome to ride around in series then have a warning go off that it's under 20% capacity, switch it to parallel and then have double the capacity to make sure that you make it home.

Thanks in advance

 

[beto_pty]

just switch between

http://www.hobbyking.com/hobbyking/store/__10264__XT60_Harness_for_2_Packs_in_Series_1pc_.html

and this

http://www.hobbyking.com/hobbyking/store/__10265__XT60_Harness_for_2_Packs_in_Parallel_1pc_.html

however....

P = IV
and assuming P (power required) is constant... (your weight/friction /losses at 10 kph)
halving your V (parallel vs series voltage ) will double your I... negating the doubling of amp hours you just obtained...

i actually did try this once with 4s vs 8s at a slowish speed like 15 kph... actually i got a better run at 8s since my batts did not unbalance so much and the amp drain was lower... it was however a slight difference; nothing earthshattering maybe 5%... I stuck in my mind cause the improved range combination was in the opposite manner as i thought it would ...

 

[mark5]

Same way as beto_pty said, you could use Anderson connectors as described here.

 

[laxplayer9009]

just switch between
View attachment 1
http://www.hobbyking.com/hobbyking/store/__10264__XT60_Harness_for_2_Packs_in_Series_1pc_.html

and this

http://www.hobbyking.com/hobbyking/store/__10265__XT60_Harness_for_2_Packs_in_Parallel_1pc_.html

however....

P = IV
and assuming P (power required) is constant... (your weight/friction /losses at 10 kph)
halving your V (parallel vs series voltage ) will double your I... negating the doubling of amp hours you just obtained...

i actually did try this once with 4s vs 8s at a slowish speed like 15 kph... actually i got a better run at 8s since my batts did not unbalance so much and the amp drain was lower... it was however a slight difference; nothing earthshattering maybe 5%... I stuck in my mind cause the improved range combination was in the opposite manner as i thought it would ...

I'll take your word for it, no need to over complicate it if un-needed.

Thank you for the response