Schultze and LiPos
 

Hi,

At first I would like to state that I am new to electrics. I recently purchased a Schultze 6-330d charger which includes the latest version of software I think it is 8.11v. After some time I managed to learn how to operate the charger which seems a robust, simple and high quality piece of hardware. However I still I try to understand the logic of the LiPo part mainly so I would like your help.

I have a KOKAM 3S 2000mAh 11.1V battery to start playing with. According to what I read LiPos have about 50% of their capacity when they come new from the factory. Do I have to discharge it before I fully charge it?

The nominal voltage of the KOKAM LiPo cell is 3.7V however the min and max recommended values from KOKAM are 2.7V and 4.2V respectively. When I discharge the battery with manual fixed discharge program D how does the charger know where to stop? Does it measure the voltage continuously and when it reaches the min 2.7Vx3=8.1V stops? If this is the case what happens if the cells are not balanced? If one for example is at 2.6V and the other at 2.8V? Do I have to monitor the charger during discharging and stop when it reaches the above values or it will stop automatically? I have exactly the same question for the charging process (Manual Fixed Charge Program C) how will it detect where to stop?

For the above battery what kind of charge and discharge rates would you use for the first cycles with the Schultze charger? Also would you set a max charge quantity value? In the manual it is recommended 10-20% of 2000mA in my case. Do you set this as recommended or leave at the 99999 value where there’s no control of the given charge quantity?

Thanks and regards,

Nik

RE: Schultze and LiPos
 

LiPolys do not have any "memory" characteristics, so you can plug them in and charge them. Discharging LiPolys under most circumstances is, IMHO, a waste of a perfectly good flight. The only time I personally would consider discharging a LiPoly is if I noticed a problem, such as a short flight, or excessive heating. That said, I have never discharged a LiPoly outside an airplane.

Your pack should have come with a set of very explicit instructions on the care and feeding of LiPolys, including proper charge and discharge rates. Follow those instructions when setting up the charger, using the charger's instructions to figure out how to change the settings, not to determine the proper charge rate for hte pack. Make sure you understand everything in those battery instructions, and follow them. Anything you read on a forum can be suspect. The instructions that came with the pack are the final authority.

Normally, you would charge LiPolys at no more than a 1C rate, that is, one times the Capacity of the pack. 2000mAh pack, 2000mA (or 2 Amp) charge rate. Charging faster could cause the pack to go overvoltage, overheat, and catch fire.