par glnc222 » Mar 21 Fév 2017 02:52
The voltage shown on the battery looks fully discharged. There is some possibility the cells are defective, but only testing can tell. They need testing whether they will charge.
It is possible a minimal voltage protection feature of the Protection Boards are tripped by the low voltage on the lithium cells, over-discharge protection.
You might make temporary bypasses of the protection boards to allow the Neato to charge half a minute, and then try it again. I had not thought of this Protection Board aspect before. The protection disconnects the battery making it appear absent to the Neato. On dock power the system runs and shows red light and "critical battery error" message over USB; sometimes there is a message to turn on the battery disconnect switch, as it produces the same condition.
Neato charging circuits may reproduce this low voltage protection internally and reject the battery to preserve it. The software is not published.
It appears the procedure normally required is a separate cell lithium battery charger to be used before assembly. After assembly another instrument, chargers for battery packs, are sold by some battery dealers, BatterySpace.com in the U.S., and on ebay. Such equipment is often used by RC racing hobbyists. A charger specifically for lithium packs is needed, with the proper voltage for the size pack. Some hobbyists are equipped with adjustable bench power supplies which could supply a suitable voltage, maybe 1v over the pack voltage, applied for half a minute only. There are some inexpensive adjustable buck voltage converter devices sold, small boards, which take a 12v supply (car battery or A/C adapter) and can adjust down to 3v, which I have as a possible alternative but never had to use. There might be some adjustable A/C adapters. The over-voltage protection board will trip if the voltage applied to each of the individual packs separately, exceeds about 8.4v (4.2v per cell). A charger will use a current regulator which raises voltage until the specific charging current of the charger (2 amps in the Neato's own charger, usually less on external chargers) is achieved. Charging terminates when the maximum voltage is reached for lithium batteries (compared to heating in NiMh charging, and 16.8v the two packs combined compared to 18.5v on NiMh Neato batteries). You can test the Lithium charging on NimH packs and see the proper termination by voltage, short of the full NiMh charge, to test the charging system.
Deeply discharged NiMh batteries will charge in red light a short time before switching to orange.
Besides separate cell chargers there are cell testers which will cycle the cells and measure their capacity to verify specifications.
[edit] If the combined packs voltage on multimeter is under 12v it is possible a brief charge can be applied with a 12v car battery, which actually delivers over 12v, assuming the protection boards are not tripped. A multimeter ammeter can be inserted in the circuit for monitoring as well. Making battery packs does require some equipment. It is not for the ordinary consumer who will buy replacements batteries such as the AnewPow products.
