How long till putting lipo's into storage mode

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Just to put this to bed and for me to understand it better. We have a battery "charged" to 8.3-8.4v and we set the cutoff to 6v so we are only using 2.4v out of the battery because why? Rather than using half?

Also my dynamite killswitch has a few settings and 2 that I remember are 3v and 6v. So like I said im trying understand lipo and proper ways to keep it safe and reliable
 
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Its because of the way a Lipo discharges...once you hit around 3v per cell...the lipo will dump its remaining power very quick. So you will severely discharge the pack making it potentially unstable. I am one of those odd guys I have my voltage alarms set for my E Revos at 3.5v or 21v for the 6s set up. The lowest I have ever set cut off or alarms too is 3.2v...or 6.4 for a 2s pack. As long as you are not dropping below 3v per cell, you should be a-ok. Here is a visual aid for ya! ??

LV91V.gif
 
Thanks Rick and thats my concern I have voltage cutoff on my dynamite kill switch set to 4v. Not sure if it was a total of 4v on the battery which I would assume it is. And when I do go to charge the battery its showing a voltage of roughly 3.6v on the charger. I don't want any mishaps lol
 
Here is a good lil tool that I use. This is a smart lipo alarm. You set the alarm voltage and it will alarm and warn you when at that voltage. It is smart in the sense on E rigs...it doesn't false alert under discharge load if your punching the throttle..only when the voltage is truly at where you set it. I don't know if it will be loud enough for our brap rigs...I will know once I run it on mine.

https://www.smc-racing.com/index.php?route=product/product&product_id=559
Rep732 said:
Thanks Rick and thats my concern I have voltage cutoff on my dynamite kill switch set to 4v. Not sure if it was a total of 4v on the battery which I would assume it is. And when I do go to charge the battery its showing a voltage of roughly 3.6v on the charger. I don't want any mishaps lol
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3.6v is more then fine..heck storage voltage is 3.8 for most lipos.
 
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RickDizzle said:
Here is a good lil tool that I use. This is a smart lipo alarm. You set the alarm voltage and it will alarm and warn you when at that voltage. It is smart in the sense on E rigs...it doesn't false alert under discharge load if your punching the throttle..only when the voltage is truly at where you set it. I don't know if it will be loud enough for our brap rigs...I will know once I run it on mine.

https://www.smc-racing.com/index.php?route=product/product&product_id=559

3.6v is more then fine..heck storage voltage is 3.7 for most lipos.
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I appreciate we're talking 100millivolts here, but storage should be 3.8v/cell.
Had the joy of storaging too many packs to know that one.
 
Twitchfast said:
I appreciate we're talking 100millivolts here, but storage should be 3.8v/cell.
Had the joy of storaging too many packs to know that one.
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You are 100% correct. 3.8v/cell. That was my fault. Sorry been a long day and I appreciate accurate info and being corrected when I am wrong. Nothing worse then giving bad info. ?? fixed my original post to prevent confusion for others.
 
Rep732 said:
It comes to measuring the milli counts :ROFLMAO: ?‍♂️
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No were dealing with 1/10 of volts. No one but the witch hunters give a shite to count down to 1/1000 of a volt. Pure paranoia. Fail sages are set to 3 volts per cell, 2s =6 volt. Time to charge. Theres no voodoo, no magic, no mystery. Go look at consumer electronics ad see what the rest of the world does with lithium batteries, we over complicate the hell out of something that is so simple that it sucks.
https://batteryuniversity.com/learn/article/premature_voltage_cut_off
https://batteryuniversity.com/learn/article/the_li_polymer_battery_substance_or_hype
Mush of the voltage cut off issues go back to when lithium tech was still new, and the market became saturated with low quality highly unstable cells. There was a steep learning curve at first because of these issues. The established 3.0 volts per cell cut off has been the industry standard for over 10 years now. doesn't matter if its lithium ion, polymer, cobalt or what ever. They share the same traits. The 3.0 volt per cell cut off it designed to allow a little bit if reserve capacity in the packs to allow for self discharge. The rc world has based its cut off voltages in the flight world where the need for reserve capacity is much higher then land or water based higher. You still need to be able to get back to base and, or land safely. So many people were so scared their birds would fall from the sky in a flame inferno they set higher cut offs as a safety net. Heck we even used to time packs under high load condition and wait for them the hit 3.2 volts per cell, note it in the battery and set a timer for allowable flight time. At 3.0 volts per cell you still have roughly 20% of reserve power left. (This is highly dependent on internal resistance, pack temp and so on) so why we beat the ever living crap out of higher cut off voltages in land based rc is beyond me. 3.0 volts per cell (like what every kill switch specs out in 1/5 scale) is perfectly safe. Conversely going over 4.2 volts per cell during charge generates too much heat and causes the gel inside the packs to start to off gas and bloat the packs. This is much more critical as pack damage has occurred, and a fire ball is much more likely then a slight over discharge. I have only ever seen voltage references beyond 1/10 of a volt when charging for maximum pack capacity. This also shortens the packs usable life span, so again a moot point. Usable voltage in lithium based batteries is 3.0 to 4.2 volts per cell. Arguably how often a pack is balanced is more important then how low the cells are taken, as you have more of a risk in shorting one cell if one is at 2.8volts and another is at 3.0 volts when the lvc kicks in. (Although 2.8 volts per cell is the lowest limit a lithium based cell can be taken, there is going to be some damage done to the pack at that voltage, ie shorter cell life.)
 
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We were doing some prototyping for a guy at the machine shop with high output "flashlights" for hunting at night. One of his big challenges was a battery with high output and had to be compact. Which lead him to do a lot of research on the topic. Part of the PC board that controlled the LEDs had a regulator built in, and a low voltage cut off/ high voltage cur off. Through the various batteries he tested he came up with a cut off voltage of 2.95 volts per cell as optimum, and had the PC board set to 3 volts per cell to allow for lazy people that didnt want to charge spent batteries right away. I was fortunate enough, That he shared a lot of his work with me on the development phase of it. Well he would show anyone that would listen to him or could understand what he was doing. He ended up going with 2 different battery systems, one was 4, 18650 Panasonic lithium ion cells for his mobile version. (Ran in series to make 4s) then he had a pack for his tripod mount unit that used lithium polymer batteries, and plugged into the lights body. His biggest concern was cell health. As he gave the same warranty on his new series of lights as his old one. Was very interesting project to be involved in. Wish I had his tables from his testing on battery performance. Really an eye opener.
 
I must say I have my low voltage cut off set to Low on my Hobbywing 1080esc, that is approx 3.1v.
I don't storage charge my Lipo's as generally they are discharged and charged almost weekly (often daily).

Sean you information is brilliant and should set a lot of minds to rest, yes Lipo batteries can be volatile, but so is petrol and we play with that endlessly.
 
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