can i run a 17ah and 13,8ah together?

[footpump]

hi all when I first had my kudos vita uno ebike back in 2014 was a bit limited by range on its 10ah battery.
I now have changed the rear hub moter to yosepower/elife shop 350w with 5 levels of pas /full speed throttle
15amp kt controller and is speed sensor.
in the past range was the main consideration, but I find with the 350w moter I like pas 4 I can happily trundle along at about 13 mph with no effort.
I have a new yosepower 17ah dolphin 09 which gives about 34 miles range using the 350w moter (ideal sunny /no wind conditions)

I also have a new enerpack softpack 13.8ah, which I have not yet tried on 350w to compare to the 17ah dolphin.

I am awaiting a kt sinewave 17 amp contrioller from ali express which is thec psw power one which I will swop out the 15amp controller.

I was going to use either the 17ah battery or 13,8 softpack but thought I might as well run them together as I want to do a trip of 40 odd miles in total and will be main roads and mybe up the 15 mph limit.

I have seen the 2 batteries should be balanced both read 41.6 v on multimeter after a full charge.
do I just connect both batteries to the y lead in photo
which I bought for joing to batteries.

thank all ps off to test enerpack.

 

[anotherkiwi]

Yes you can do that. When the smaller battery is empty the LVC of the BMS should turn it off leaving you with what is left in the big one. But I think you will be back home before that ever happens.

30.8 Ah x 36 v = 1.1 kWh

At 10 Wh per km that would be 110 km
At 12 Wh per km that would be 92.5 km (57 miles)

When I am feeling lazy I use about 7.8 Wh / km which would give me a range of 142 km with those two batteries.

 

[Deleted member 4366]

you must disconnect one of them during charging, otherwise one will charge the other through the discharge terminals, which by-passes the charge safety controls.

 

[footpump]

thanks all

might swop connections on my 250w tdz2 bike to take the 17ah and softpack should get even more range?