LiPO battery taking long time to charge

[Engineface RC]

Hello, I am new to forums, so I am not sure if I am making this post correctly. (Just wanted to say that) Anyways, I bought an HRB 2s LiPO off of Amazon, since all the reviews seemed really good. When I got it, I plugged it in right away and started balance charging it with my Traxxas Ez Peak Plus charger. After a while it stopped charging and the light on the charger was flashing red. The battery and charger were both not hot, so I plugged it in again and continued charging it. It eventually finished charging so I used it in my Traxxas for a while, but when I tried balancing it again, the same thing happened. What is going on, and how can I fix this? (If I can)

 

[RustyUs]

Which LED(s) were flashing on the charger?

 

[pug]

Get a better charger. I had an EZ Peak Plus before, it’s terrible. You can’t monitor the battery voltage or anything. I sold it then bought a Hitec RDX1 Pro, it’s absolutely amazing.

 

[Engineface RC]

Which LED(s) were flashing on the charger?

2a

 

[pug]

2a

Read the manual error codes. Check the cell voltages, one cell may be dead.

 

[Tunedfrog]

It's the charger. I have two Traxxas EZ chargers I bought in a lot and they do the same thing once in a while.
I am going to purchase a good one, one of these days.

 

[The_RC_Dude]

Hello, I am new to forums, so I am not sure if I am making this post correctly. (Just wanted to say that) Anyways, I bought an HRB 2s LiPO off of Amazon, since all the reviews seemed really good. When I got it, I plugged it in right away and started balance charging it with my Traxxas Ez Peak Plus charger. After a while it stopped charging and the light on the charger was flashing red. The battery and charger were both not hot, so I plugged it in again and continued charging it. It eventually finished charging so I used it in my Traxxas for a while, but when I tried balancing it again, the same thing happened. What is going on, and how can I fix this? (If I can)

I'd say there's either something wrong with your charger or a battery, do you have any way to check the voltage of the battery? You can charge it best you can then test the voltage, if it reads something close to 4.2 volts per cell or 8.4v for the whole pack voltage, then you're good and it's the charger. Also check the balance of the cells, they should be within <0.03 volts from each other, so if it reads, say, 3.73 for the first cell, and 3.74 for the second you're good, but if the second cell reads, say 3.69 then they are significantly out of balance, and you need to balance them via the charger. You may need/want a new or better charger, I'm not going to push you toward a specific charger though. Right now I have a very basic balance charger, the SkyRC E3 (charges 2-3s LiPos). Probably am going to upgrade to a better/fast charger sometime, preferably one with a screen/readout of the battery ratings.

Anyway, welcome to the forum!

Also, make sure your charger is in the "LiPo" mode, not sure if that charger is always in LiPo mode or not, but if it's in NiMh mode then that could be causing issues. If you don't have a way to check the voltage of the pack, I recommend getting a LiPo alarm/buzzer and/or a multimeter, I have a LiPo buzzer/alarm, it tells me the voltage of each cell and of the whole pack, plus it'll beep loudly when the voltage of the pack goes under the cut-off voltage that the user set (you can set it anywhere from 2.7v to 3.8v, I prefer 3.4v cutoff). They are a GREAT tool, super small, you'll probably be able to fit it in your rig when running (leave it connected and it'll monito the voltage, that's how it's desgined), and they are CHEAP too, at ~<$5!!

 

[RustyUs]

2a

More than likely the charger's timeout setting is set low (non adjustable on that charger). With a charger that has a lower balance charging capabilities, in the constant voltage (ConstantCurrent/ConstantVoltage) part of a balance charge, a LiPo battery pack may need an extra long time to balance the cells if the cells are aging at different rates.

I've had a number of older LiPo packs take forever to finalize a balance charge, because the internal resistance of one cell is higher than the other(s).


Moving forward... having a charger that gives you a readout of each cell's voltage would be recommended. Also, it is very common nowadays, for chargers to include internal resistance (IR) readings of cells. Even though the readings are not highly accurate, they will show a person that a cell, in a pack, is possibly aging at different rates than the rest. The IR readings should only be used as a tool as there are a lot of factors that affect internal resistance.

 

[tntpoof]

a better charger will correct this problem..

 

[Engineface RC]

I'd say there's either something wrong with your charger or a battery, do you have any way to check the voltage of the battery? You can charge it best you can then test the voltage, if it reads something close to 4.2 volts per cell or 8.4v for the whole pack voltage, then you're good and it's the charger. Also check the balance of the cells, they should be within <0.03 volts from each other, so if it reads, say, 3.73 for the first cell, and 3.74 for the second you're good, but if the second cell reads, say 3.69 then they are significantly out of balance, and you need to balance them via the charger. You may need/want a new or better charger, I'm not going to push you toward a specific charger though. Right now I have a very basic balance charger, the SkyRC E3 (charges 2-3s LiPos). Probably am going to upgrade to a better/fast charger sometime, preferably one with a screen/readout of the battery ratings.

Anyway, welcome to the forum!

Also, make sure your charger is in the "LiPo" mode, not sure if that charger is always in LiPo mode or not, but if it's in NiMh mode then that could be causing issues. If you don't have a way to check the voltage of the pack, I recommend getting a LiPo alarm/buzzer and/or a multimeter, I have a LiPo buzzer/alarm, it tells me the voltage of each cell and of the whole pack, plus it'll beep loudly when the voltage of the pack goes under the cut-off voltage that the user set (you can set it anywhere from 2.7v to 3.8v, I prefer 3.4v cutoff). They are a GREAT tool, super small, you'll probably be able to fit it in your rig when running (leave it connected and it'll monito the voltage, that's how it's desgined), and they are CHEAP too, at ~<$5!!

The charger is fine, I tried it with my other Traxxas made batteries and it works great. Must be the battery. Or maybe the charger is only made for only traxxas batteries. I don’t currently have a cell checker, but I definitely should get one! Someone suggested that a cell might be dead. The thing I don’t understand is the battery works fine when I am using it in my RCs. I think I will see if I can return the battery and get a better one, HRBs are cheap anyways. Thank you for answering, it helped my understanding.

 

[Greywolf74]

Its probably a combination of the charger and one of the cells being weaker than the rest. I hate to say it but the Traxxas charger is terrible. You should really get one that can show you voltages and IRs at the very least. Just my .02

 

[pug]

Its probably a combination of the charger and one of the cells being weaker than the rest. I hate to say it but the Traxxas charger is terrible. You should really get one that can show you voltages and IRs at the very least. Just my .02

Yeah, in my experience, the Traxxas chargers are pretty garbage, I sold mine and bought a Hitec RDX1 Pro which is infinitely better than the Traxxas charger.

 

[The_RC_Dude]

The charger is fine, I tried it with my other Traxxas made batteries and it works great. Must be the battery. Or maybe the charger is only made for only traxxas batteries. I don’t currently have a cell checker, but I definitely should get one! Someone suggested that a cell might be dead. The thing I don’t understand is the battery works fine when I am using it in my RCs. I think I will see if I can return the battery and get a better one, HRBs are cheap anyways. Thank you for answering, it helped my understanding.

Ok then. Don't the more recent Traxxas packs/chargers have their new proprietary main-battery-plug-plus-balance-connector thing, where the main plug is integrated with the balance connector? If so, and you're using an xyz-to-Traxxas battery plug convertor, that wouldn't work. The charger might be trying to charge your HBR pack through the main plug, which wouldn't be good. The little stock blue 2s 1500mah LiPo that came with my car was acting up half a year ago, the cells were getting un-balanced and the voltage was all wonky, and my charger wouldn't take it either. To be fair, it was probably near the end of it's life, it did survive me as a total noob to RC when I first got my buggy. The red positive wire came un-soldered too on the balance connector, so it's pretty much useless.

You're welcome, glad I could help!

More than likely the charger's timeout setting is set low (non adjustable on that charger). With a charger that has a lower balance charging capabilities, in the constant voltage (ConstantCurrent/ConstantVoltage) part of a balance charge, a LiPo battery pack may need an extra long time to balance the cells if the cells are aging at different rates.

I've had a number of older LiPo packs take forever to finalize a balance charge, because the internal resistance of one cell is higher than the other(s).


Moving forward... having a charger that gives you a readout of each cell's voltage would be recommended. Also, it is very common nowadays, for chargers to include internal resistance (IR) readings of cells. Even though the readings are not highly accurate, they will show a person that a cell, in a pack, is possibly aging at different rates than the rest. The IR readings should only be used as a tool as there are a lot of factors that affect internal resistance.

Not to hijack the thread here, but you mean that some chargers will only do the "balancing" for a set time, and others will do it for longer, possibly balancing the cells on an older/higher IR pack longer? Cool!

 

[pug]

Ok then. Don't the more recent Traxxas packs/chargers have their new proprietary main-battery-plug-plus-balance-connector thing, where the main plug is integrated with the balance connector? If so, and you're using an xyz-to-Traxxas battery plug convertor, that wouldn't work. The charger might be trying to charge your HBR pack through the main plug, which wouldn't be good. The little stock blue 2s 1500mah LiPo that came with my car was acting up half a year ago, the cells were getting un-balanced and the voltage was all wonky, and my charger wouldn't take it either. To be fair, it was probably near the end of it's life, it did survive me as a total noob to RC when I first got my buggy. The red positive wire came un-soldered too on the balance connector, so it's pretty much useless.

You're welcome, glad I could help!

Not to hijack the thread here, but you mean that some chargers will only do the "balancing" for a set time, and others will do it for longer, possibly balancing the cells on an older/higher IR pack longer? Cool!

I noticed that a newer Zeee 3s 5200 mah balances faster than my almost a year old POVWAY 3s 5200 mah on a Hitec RDX1 Pro.

 

[The_RC_Dude]

I noticed that a newer Zeee 3s 5200 mah balances faster than my almost a year old POVWAY 3s 5200 mah on a Hitec RDX1 Pro.

That makes sense, after all (after the initial <10 cycle break in period) the new LiPo is...newer, so it's fast and the cells are balanced better. LiPos have a certain life span, after that they will puff, not take a charge, ect.

 

[pug]

That makes sense, after all (after the initial <10 cycle break in period) the new LiPo is...newer, so it's fast and the cells are balanced better. LiPos have a certain life span, after that they will puff, not take a charge, ect.

Yeah, the Zeee doesn’t even have 10 cycles on it yet.

 

[The_RC_Dude]

Yeah, the Zeee doesn’t even have 10 cycles on it yet.

Expect the performance to increase slightly (including faster charging) after a few more cycles then.

 

[Greywolf74]

Some lipos will charge faster than others even when they are brand new even if they are identical packs. Theres a bit of a lottery system involved with LiPos. Its very much similar to the silicone lottery in computer CPUs and GPUs if your familiar with that.