Lipo cell memory question..

[InFlames]

Is it okay to recharge a lipo that is only about half dead?

[cartronicshn]

yup, just top it of and make sure you balance the pack while you are at it

[Grumpster1980]

LiPo's do NOT have a memory effect like Ni-Cd's did. You can top off your batteries with out worry.

[InFlames]

Originally Posted by cartronicshn

yup, just top it of and make sure you balance the pack while you are at it

Originally Posted by Grumpster1980

LiPo's do NOT have a memory effect like Ni-Cd's did. You can top off your batteries with out worry.

Cool, thanks guys. And i balance every time.

[SRQmini]

Originally Posted by cartronicshn

yup, just top it of and make sure you balance the pack while you are at it

So what if I have a Losi MRC with the Lipo & charger that came with it?
The charger is pretty basic, does that mean it automatically balances it? Or it doesn't get balanced? What does balancing do?

[Grumpster1980]

Originally Posted by SRQmini

So what if I have a Losi MRC with the Lipo & charger that came with it?
The charger is pretty basic, does that mean it automatically balances it? Or it doesn't get balanced? What does balancing do?

Not sure what your charger looks like or the features it has but Ballancing your batteries makes each cell the same voltage, prolongs the batteries life, and gives you longer run times.

Lipos have two connectors on them one is for ballancing the other is for connecting to your ESC for power to your RC.

You can get a quality charger for a reasonable price that will let you ballance charge all of your lipos and you older NiMh or Ni-Cd batteries.

The Thunder AC6 is a great charger for a good price. Google it.

[Lorents]

So what if I have a Losi MRC with the Lipo & charger that came with it?

The batteries that comes with the MRC are NiMH and not lipo so you dont have to worry about balancing.

[zdaddy]

What happens if you never balance a Lipo?

[EddieO]

All batteries have a memory effect....Lithium based batteries just have less profound effect, which makes it hard to cause or notice....

Later EddieO

[Grumpster1980]

Originally Posted by EddieO

All batteries have a memory effect....Lithium based batteries just have less profound effect, which makes it hard to cause or notice....

Later EddieO

Where are you getting your information from? because everything I have read states that lipos do not have a memory effect.

Read here: http://www.rchobbies.org/lithium_bat...eakthrough.htm and countless other web sites. "LiPos don't develop memory or voltage depression characteristics like Ni-Cds. Do charge them without the worry of cycling or discharging them."

[Lorents]

What happens if you never balance a Lipo?

Worst case is a lipo fire... The thing is that the cells that your pack is made up from is not 100% matched and after numerous charge/discharge cycles one of the cells tend to have higher voltage than the other. With lipos this is a bad thing because if you are charging a 2S pack without balancer the charger is going to keep charging until it detects 8.4 volts on the pack - if the cells are 0.4 volts out of ballance one cell would be at 4 volts an the other at 4.4 volts. When a cell gets charged above 4.2 volts it will get hot and could catch on fire. If you are charging without a balancer its a good idea to keep an eye on the temperature of the pack and use a lipo bag.

[Sharkey]

keeping an eye on the temps and using a lipo bag are 2 things you should do anyways.

a friend of mine does not use a balancer, his charger doesnt have it built in and he hasnt gotten one (i keep telling him to). we run together all the time, so i make sure that anytime we run that before charging, before we run the pack and once its dead, and again at storage voltage, i check manually with a voltmeter to see how balanced the pack is. so far the most it has ever been out is 0.01v. to me that shows that the packs are good quality. a poor quality pack will go out of balance quickly. and jus in case the pack goes way out of balance i do have the adapter to balance charge them with my charger.

so a lipo can be run without balance charging but you need to pay very close attention to it. charging without a balancer does increase the risk.

[sudden_scaler]

dont topoff a lipo more than twice without discharging it btw....

[Lorents]

dont topoff a lipo more than twice without discharging it btw....

No need to do that with lipos. They dont have significant memory effect, and should not be discharged below a certain level.

[EddieO]

Google and I am sure you will find articles...

Look not further though than Lithium based batteries for your cell phone, laptop, etc....

The Memory effect is very small compared to NiCad or NIMH based batteries.....but its still there, but basically unnoticiable.

As for RC companies stating it, well, they don't make the batteries....so don't go trusting statements they make on how the tech actually works.....they know little on how the stuff is even made usually.

Remember, NIMH when first introduced to RC was supposed to be memory free too! It was less than NicAd

Later EddieO

[Sharkey]

lipos deffinitly have memory, however in their normal operating range (4.2-3.0 volts) its almost unnoticable. discharge one below 3.0 volts and the memory will become aparent. you may be able to bump the voltage back up to charge it, and the battery may work fine after, but its not going ot have the punch it once had.