stunthanger.com

Electric Stunt => Gettin all AMP'ed up! => Topic started by: Motorman on December 25, 2021, 12:53:23 PM

Title: Blank
Post by: Motorman on December 25, 2021, 12:53:23 PM
Blank
Title: Re: New Battery Conditioning
Post by: Ken Culbertson on December 25, 2021, 01:30:08 PM
I don't think taking them out of storage voltage then putting them back does much of anything.  If they need to be taken out of storage periodically then how would the manufacturer be able to store and ship them?  Personally I keep mine in a refrigerator and I have kept them fully charged for as much as two weeks and in storage untouched for nearly a year with no problems.  For all of this I will probably be charged with battery abuse and arrested.

Ken

Title: Re: New Battery Conditioning
Post by: Dennis Toth on December 25, 2021, 09:05:48 PM
When I first started in electric I would come home from flying and charge the packs and record the mah used. These were Thunder Power battery packs and after several months they started to buff. I later learned that storing them at full charge was the cause of the puffing. Now I fly and don't charge until the night before I intend to fly. None have puff in a couple years doing it this way.

They use to do a break-in with the very early batteries but for current day batteries the loads we apply to the packs, no break-in is needed. For very high amp use applications some mild cycling before full power might be useful but not for our loads.

Best,    DennisT

Title: Re: New Battery Conditioning
Post by: William DeMauro on December 26, 2021, 10:30:31 AM
Most new batteries when shipped are at 30% charged. When they come I check them and make sure I did not get any bad batteries. I usually charge them up to full at 1c then bring them back down to storage (50%) at around 1 c discharge and leave them like that till I am ready to use it. I have not had any problems doing things this way. I do this mostly because I do not trust leaving them at 30% charge for long periods of time. I have batteries that are 3-4 years old that still work well so I don't change things up much.
Title: Re: New Battery Conditioning
Post by: Fred Underwood on December 26, 2021, 12:36:15 PM
ThunderPower used to show a break in procedure on their site.  Basically, it involved slow partially charging and 3 - 5C discharge. They suggested a couple of these light cycles not up to 100% nor down to 20%.  I couldn't find the suggestion or procedure on their site now, so they may not recommend it any longer.

If batteries puff when cold, I might wonder how much charge they had.  PowerLab chargers will not fully charge if below 55°, unless you override.  Of course you need a temperature probe for the battery or the charger senses its own temperature.  I have the problem when my batteries are warm in the house, and my charger is sitting the garage and decides that it is too cold.  Battery capacity is lower in cold, so a full 4.2v battery is overcharged if allowed to fully cool to below 55°.  If you go to fly in cool temperature it takes a long time to cool the battery below that temperature, so not generally a problem to have a fully charged battery.  Or you can use a battery warmer.

If you store the battery in the refrigerator, it also takes hours to warm the center of the pack for charging.

Just a repeat of "facts" that I have read, no real expertise.
Title: Re: New Battery Conditioning
Post by: Rick Wetzel on December 30, 2021, 12:04:56 PM
On one of the RC forums I read about a break-in procedure I recently tried with a number of new batteries.  I lost the link but I think I can essentially remember the procedure:
1. Fully charge the battery at no more than 1S.  Let the battery sit overnight, or at least for about 8 hours if possible.
2. Discharge the battery to a safe storage level, roughly 3.80V per cell.  Discharge slowly; I think I was discharging at less than 1S; for example, I was discharging at .2A on a 3300mAh pack. Let sit overnight, or about 8 hours at minimum.
3. Repeat step 1.
4. Discharge the battery as in step 2, except discharge to 3.50V per cell. Let sit overnight, or about 8 hours at minimum.
5. Repeat step 1.
6. Discharge each cell close to completely discharged. My charger won't let any cell get below 3.30V per cell, even though full discharge would be about 3.20V per cell. Check your charger as you may be able to limit the minimum voltage per cell.  You need to carefully watch the battery as it gets close to full discharge just to make sure.  Let sit overnight, or about 8 hours at minimum.
7. Recharge to storage voltage of about 3.80V per cell, and leave the pack alone until you're ready to fly. You can recharge at 1S this time.

The thought process around this break-in procedure is that it allows the chemistry of each battery to better adapt to being charged and discharged, and slightly reduces the resistance of the battery, which should reduce the heat generated during a discharge while flying.

This process is somewhat time consuming. I work at home, and just followed the process each day, keeping an eye on the batteries during each cycle. I use a Horizon Ultra P4 charger, charging and discharging four cells at a time.

I've never had any batteries swell up.  I keep my batteries at room temperature in the off-season, and never charge them above 1S.  Overly rapid charging and over discharging of batteries are the main causes of swelling of the packs.

I saw other replies to this string indicating that folks charge the packs the night before flying, which I also do and have had few problems with. If you can "top off" the batteries in the morning, that is also a good idea.

Hope this is helpful!

Rick