A couple basic questions regarding Charging/Batteries

vislaw

Member
I have a ProtekRC SuperPro 1000 power supply with adjustable voltage 12-30V and I'm powering a Thunder Power TP820CD dual port charger. The charger accepts 10.5 to 28 volts with input current drawing up to 40 Amps. I want to do parallel charging doing 6 5000A 4S Gens Ace batteries at a time.

My question involves the variable voltage setting of the Power Supply. On its specs I see that it lists its current as 25A @ 30V and 37A @ 12V. I must confess to having forgotten most of what I learned about voltage and amps from my old science courses so please forgive my ignorance here. Given that the charger accepts a wide range of voltage and the power supply has a variable voltage capability, what is the best setting for the power supply in this case? Given that the specs say that it delivers higher amps at a lower voltage does that mean I should opt for lowering the voltage? Is there an advantage to a higher voltage setting that I am not aware of?

My next question involves storage of charged batteries. I have seen conflicting info regarding storing batteries fully charged. Some people say they get full power and punch by keeping batteries fully charged for a couple of weeks. However, the manual for my charger says to not keep a battery fully charged for more than a few hours. Is there a consensus on this issue? Obviously, it would be nice to be ready to fly on short notice, but I want to maximize the battery life as well as safety.
 

kloner

Aerial DP
when your charging 6x 5000mah anything, your looking at 30 amps out to make it charge at 1c. you will want to crank that power supply all the way up, the carger will output what it can from the available current

I have a pretty "lipo chemistry" smart friend, stole this from a post of his. It's not so much opinions as science

If I'm not flying my LiPo packs how should I store them?

Discharge the packs to about a 1/2 to 1/3 charge of the total capacity. Do not store batteries fully charged, cells will most likely degrade if fully charged and stored for a long period of time.
Lithium chemistries have a nominal life span of 2 years or around 200 cycles. When possible write the date you bought your packs on them, and even better keep a flight log of each pack. This way you will know when a battery pack is becoming a bit long in the tooth.

If storing LiPo batteries for the winter season, it is best to store them below room temperature. This temperature is between and 25C~77F or 0C~32F. Do not store LiPo packs at extremely cold temperatures: It is best to keep the storage temperature greater than -4F (-20C). The electrolyte in the chemical makeup will freeze at approximately -40F (-40C).

Below you will find a chart of estimated battery deterioration during storage at various temperatures.

Storage Temperature-------------40% Charge-------------------------100% Charge
__________________________________________________ ___________________________________
0 °C (32 °F) ----------------------- 2% loss after 1 year---------------6% loss after 1 year
25 °C (77 °F)-----------------------4% loss after 1 year---------------20% loss after 1 year
40 °C (104 °F)---------------------15% loss after 1 year--------------35% loss after 1 year
60 °C (140 °F)---------------------25% loss after 1 year--------------40% loss after 1 year


NEVER store LiPo battery packs at temperatures above 140F (60C), damage to cells may happen.

These results may vary with individual battery packs.
 
Last edited by a moderator:

Top