Lipo Question
#1
Lipo Question
Hi,
I have a lipo question. I am trying to build a lipo discharger by using a resistor. but im trying to calculate how many ohms and watts i need the resistor. but im am confused on the C rating of the lipo pack. I know that the C rating is the safe amount of current used to discharge the Battery. For example, if you have a 6000mah lipo rated at 20C, you can safely draw 6000mah/1000 * 20C which is 120AMPs. this is where i am confused. 120AMPs IS A LOT. So, that means if my am using a 5S setup, the power consumptions discharging at 20c is P = V*I = 18.5v * 120A = 2,220 WATTS.... What the heck am I doing wrong here? My calculation is making ZERO since. Please help1!!
I have a lipo question. I am trying to build a lipo discharger by using a resistor. but im trying to calculate how many ohms and watts i need the resistor. but im am confused on the C rating of the lipo pack. I know that the C rating is the safe amount of current used to discharge the Battery. For example, if you have a 6000mah lipo rated at 20C, you can safely draw 6000mah/1000 * 20C which is 120AMPs. this is where i am confused. 120AMPs IS A LOT. So, that means if my am using a 5S setup, the power consumptions discharging at 20c is P = V*I = 18.5v * 120A = 2,220 WATTS.... What the heck am I doing wrong here? My calculation is making ZERO since. Please help1!!
#2
Why are you trying to discharge a lipo battery in the first place???
#4
For one you don't need to apply a full 30C discharge to simply store your lipos. Secondly you should NEVER discharge a lipo without some form of cutoff. In this case you need something that can adjust the cutoff for 3.8volts a cell.
#7
Tech Elite
iTrader: (26)
Sounds to me like you are a bit out of your depth...you are much more likely to damage your lipos fiddling about like this than you are storing them at 100%. Either don't charge them quite all the way before storing or run them a bit first. What kind of charger do you have? Doesn't it have discharge capability?
#8
Sounds to me like you are a bit out of your depth...you are much more likely to damage your lipos fiddling about like this than you are storing them at 100%. Either don't charge them quite all the way before storing or run them a bit first. What kind of charger do you have? Doesn't it have discharge capability?
#9
Tech Adept
iTrader: (8)
Have you checked out the Thunder Power TP-610C charger?
It has a discharge function, plus it has a 50% "storage" charge option. There are multiple failsafe features built in to prevent Lipo damage/balance problems. (Read; Idiot proofing.) It also charges up to 10amps! I think it's a great charger for it's $130 pricetag.
It has a discharge function, plus it has a 50% "storage" charge option. There are multiple failsafe features built in to prevent Lipo damage/balance problems. (Read; Idiot proofing.) It also charges up to 10amps! I think it's a great charger for it's $130 pricetag.
#10
Teeforb - Your new ride is looking good. As for discharging lipos - as already said - I wouldn't bother. You're not even storing them that long - you'll be out racing in a week when this weather goes away right?
#12
You're over thinking it. Just take the battery out of the car after the last race of the day and put it away. There's plenty of charge left in it after a race for storage. I have left my lipos partially charged in storage all summer with no ill effects.
#14
Tech Lord
iTrader: (21)
I'm in the same deal, but with a 0610iNet charger - updating firmware does not add a real discharge function. I don't remember which update added it, but 0610iNet and the original DUO added a 300ma discharge capability and its only intent is for the storage/TCS function. If you specify a value thats less than your batt has, then the DUO/0610i will discharge at 300ma until it reaches appropriate voltage for the storage you specified.
The new DUO II and 0720iNet chargers have a true discharger with an 80watt discharge capability.
The new DUO II and 0720iNet chargers have a true discharger with an 80watt discharge capability.
#15
I'm in the same deal, but with a 0610iNet charger - updating firmware does not add a real discharge function. I don't remember which update added it, but 0610iNet and the original DUO added a 300ma discharge capability and its only intent is for the storage/TCS function. If you specify a value thats less than your batt has, then the DUO/0610i will discharge at 300ma until it reaches appropriate voltage for the storage you specified.
The new DUO II and 0720iNet chargers have a true discharger with an 80watt discharge capability.
The new DUO II and 0720iNet chargers have a true discharger with an 80watt discharge capability.