On 9/1/2014 7:32 AM, Mike Marlow wrote:
Leon wrote:
On 8/31/2014 7:17 PM, Mike Marlow wrote:
Bill wrote:
James wrote:
HI Group, I have three Ridgid li-ion batteries that I'm considering
rebuilding. Has anyone done this? I've rebuilt Ni-cad battery packs
without any difficulty but haven't dealt with Li-ion before. JIm

My initial reaction is that doing that sounds potentially dangerous,
but you must understand what you are doing!


Not potentially dangerous at all Bill as long as you have the right
charger. If the batteries are registered for the lifetime warranty
though, it could be a waste of time since they'll be replaced for
free under the warranty.

Actually overhauling L-Ion battery cells are not as easy as simply
replacing cells. Most rebuild places do not deal with these type
batteries as each cell needs to be tested to be comparable with the
other cells that they will be mated with. It is more than simply
using the correct smart charger.

Yes - it is. Oversimplification on my part in my previous answer to Bill.
It does seem that more rebuild guys are saying they won't do L-Ion these
days - or maybe it just seems that it's more of them. Seemed to me that
when L-Ion first came out most of these guys were offering to upgrade old
NiCad packs to L-Ion. I haven't seen any commentary on a requirement to
pair cells, so if that's true it comes as news to me. Sourcing the
batteries can still be a bit of a task though.


From what I have read else where and which is backed up by the Prime
cell site is that the batteries circuitry controls whether the battery
cells will receive a charge or not depending on its current voltage,
temperature. If you put in a mix of cells that are not very close to
the same voltage to begin with the charger may not properly charge all
of the cells. I have also read, in at least where the better battery
brands are concerned the cells used are each tested so that they all
have very similar voltages when grouped to become a battery. Not a
problem if you have hundreds or thousands on hand. If an individual
buys 4~5, 3.6 to 4.1 volt cells, for the typical cordless drill he may
actually need many more to get a close voltage match to begin with.
This is doable but not practical for the occasional battery rebuild.
And while you see this being done the results probably are not going to
be a good solution long term. If the cells are not properly matched to
begin with the life span for the unit probably is not going to be as
long. I suspect that when you have to stand behind your product the
extra expense of testing and grouping these cells might be the reason
that you don't easily find a battery rebuild business that has been
around for an extended length of time rebuilding the Li-Ion batteries.