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Thread: Need some help Charging lipos Reply to Thread

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[QUOTE=philipa_240sx;954087]1C charge is always the safest bet.  I still recommend 1C rates, especially for unknown or generic brands that are not specifically rated for high charge rates.

Quality Lipo's like Gens Ace, Hyperion, and Thunderpower are rated at 5C charge rates and above.  They do not degrade at these higher charge rates, even over the long term:

Source: [URL="http://www.hyperion-world.com/products/product/HP-LG325-0850-2S"]Hyperion[/URL]

A quality charger is also a must for safe and reliable charging.  The OP's iCharger is good as is Thunderpower, Hyperion, Bantam, and Revolectrix to name a few.

Another technique I like to use is capacity charging.  Hyperion has evidence to suggest charging to 90-95% capacity instead of 100% can extend Lipo lifespan as well as speeding up the charge process:

From the Hyperion EOS Charger manual:

My Hyperion charger has a capacity setting which uses pack voltage and rated capacity to determine how much charge is in the pack.  I use the 95% setting all the time and it saves a considerable amount of time during the charge.[/QUOTE]

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Topic Review (Newest First)

06-03-2012 06:01 PM

maxx

Re: Need some help Charging lipos

Quote:

Originally Posted by Arceenut

New to LiPos. Please explain to me what the detriments are in storing batteries fully charged? One of the advantages (as told to me) is that LiPos do not self discharge and will hold their charge over long periods. This storing at half/third charge defeats the "instantly available" feature that seems to be one of the advantages of this type of battery.

According Mr. Lucien Miller, the electric engineering guru in the RC world, the chemical substance is in a high energy and unstable state when a lipo pack is fully charged. The electrons have a strong tendency to flow but are being held back until a loop is formed.

I imagine this will cause some fatigue and thus have a greater potential to damage the battery?

Anyway, my experience seems to suggest fully-charged state is not that detrimental to lipo batteries, while overcharge and over-discharge are. Overcharging is dangerous and can cause explosion/fire. That's why using an accurate charger is very important. When you buy chargers, you can give up bells and whistles but not the cut-off voltage accuracy. High-end chargers allow you to set your own cut-off voltage. It may be a good idea to set your cut-off voltage to a little lower than 4.20v, to give some room for errors caused by inaccuracy of the charger. To fly 15 seconds less each flight is not such a big price to pay for longer battery life and better safety. Over-discharging is also a big no-no. It can easily kill your battery and make it totally unusable.

With a little care, I think even a cheap battery can power hundrends of flights.

06-03-2012 04:42 PM

Riddick

Re: Need some help Charging lipos

My chargers have a storage charge option that charges to 11.6v for a 3 cell. If you don't do any winter flying then this is for you. As mentioned above, keeping your lipos fully charged for months at a time may damage the cells. During the winter months, I like to cycle all my batteries once a month even Ni cad's and Ni mh's, But this is just the OCD in me.

06-03-2012 12:26 PM

Arceenut

Re: Need some help Charging lipos

06-03-2012 12:14 PM

maxx

Re: Need some help Charging lipos

Quote:

Originally Posted by Riddick

I guess the only advantage of charging at a higher C rate is shorter charge times. Thats good if your at the field and do it a few times to get more flights in but I would stick to the 1C charge rule and just get a few more batteries.

Agree.

If you do parallel charging with your multiple packs, it's gonna be as fast.

06-03-2012 11:40 AM

Riddick

Re: Need some help Charging lipos

06-03-2012 11:29 AM

maxx

Re: Need some help Charging lipos

Looks like the concensus is to charge your lipos at 1c even if your lipos can take 5c.

It was simple because all lipo suppliers advised us to charge at 1c. With the newer generations of lipos, we are not told that we can charge at 2C, 3C, up to 6C, etc., but I am not persuaded yet.

I find nowadays, if I am careful and stay within parameters, cheap and low-end lipos are good enough for my applications (fixed-wing aerobatic flying).

06-02-2012 08:54 PM

ctdang

Re: Need some help Charging lipos

Ok perfect understood now thanks you all!

06-02-2012 08:20 PM

faron

Re: Need some help Charging lipos

1C on a 4000mah=4 amps charge
1C on a 3000 =3 amps
1C on a 2000 =2 amps
1C on a 1000 = you answer ok ok it's 1 amp

See the pattern?

So you want to charge at 5C times that. With your 4000 1C=4amps. 5Cx4amps=20amps
you can't do 20 amps because you have a 10 amp max charger

So do 2C which is 4amps x2=8amps
Select 8amps on the charger
I would still select 1C and charge over night

I hope this helps

06-02-2012 07:06 PM

Daren71

Re: Need some help Charging lipos

Quote:

Originally Posted by ctdang

one last question guys So if 5s 4000mah if charging at 1 c on the charger do i charge it at 2a .?

1c on a 4000 mah 5s is 4.0 amps.

More good reading on this link.

http://www.tjinguytech.com/charging-...po-terminology

Daren

06-02-2012 06:51 PM

ctdang

Re: Need some help Charging lipos

one last question guys So if 5s 4000mah if charging at 1 c on the charger do i charge it at 2a .?

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