Hybrid 18650 Pack?

[titusmc]

I'm currently thinking about building a 14s8p pack from a combination of reclaimed laptop 18650 cells (capacity and IR tested/matched) and Samsung 20Q cells extracted from RYOBI One+ power tool batteries I recently bought at Home Depot (2-pack of 18v 4Ah for $99 - not bad). The plan is basically to have properly matched 14s7p of laptop cells (since they are free for me) and 14s1p of the new (unused) Samsung 20Q cells, but together as one 14s8p pack (with a single 14s BMS). I'm thinking this will act as a hybrid pack that gives both decent acceleration (low voltage sag) and long range.

Is this a good idea? What, if any, safety concerns am I overlooking?

P.S. Longer term I plan on building 14s8p from entirely new Sanyo NCR18650GA.

 

[titusmc]

I suppose I should have mentioned I am using a 1000W DD Front Hub Motor (the cheapest eBay kit I could find) with a no-name 20A 48V controller. This setup has served me very well for over 650 miles so far using a 13s7p pack of reclaimed laptop cells.

The bike is a 2003 Trek 4500 with a Surly Instigator fork.

 

[KarlJ]

YES 14*8 is pushing lappie cells at 20A discharge

yes i agree should be OK although lappie cells will still cop a beating as will the good ones.

Let us know how you go or.... simply build a 30AH pack of lappie cells gives 30 x 50+V for 1500W and will go a long way to boot.
(just a little heavy but at "free" vs "$5+" i'd cop the weight penalty)