Lithium Ion battery charger

as per some recommendations regarding the proper battery charger to use with the lithium ion battery on my shutter control, I purchased the the C-TEK lithium ion battery charger. In charging the Dakota lithium battery, the charge would appear fine, but after reaching the pulse (maintenance) level the charger would go to the fault indicator. I assumed that the battery was bad as it has full discharged previously. The battery was actually bad as it became full discharged after raising the shutter.

I then purchased a new lithium battery, hoping that this would solve the problem. After reaching a full charge, the same thing happened, with the charger going to the same fault. C-Tek said it must be a faulty battery and Dakota Lithium was kind enough to provide a replacement battery.

Unfortunately, this did not solve the problem, as the new battery had the same failure. Accordingly, I have a couple of questions.

1) Has anyone else has similar problems with the c-tek battery charger? 2) will the original Black & Decker that came with the shutter damage the lithium battery?

3) there are a number of “bare bones” battery lithium battery chargers from Dakota lithium, Batteries plus Bulbs, etc. each of these are around $30. Are these sufficient? 4) Does anyone have other recommendations.

I still have a warranty question out there with c-tek, but I just want a system that operates properly, with no more dead batteries.

thank you for any responses.

Bill Hansen