Lipo Battery Charging

[Rich B]

Hi guys, I have a few questions regarding charging Lipo batteries. I will be using a 3S 2200mAh 30C battery as the model. If a manufacture states that a battery could be charged up to 3C does that mean a charger could be set the following ways on 3S?
1C - 2.2A
2C - 4.4A
3C - 6.6A
Next, if using a parallel charging board will the batteries all need to have the same mAh, cell count, and C discharge variables? So if you have a two 3S 2200mAh 30C charging; you would not want to put a 3S 1800mAh 20C on the charging board with those? I just want to have a better understanding on this .

Thanks,
Rich B

 

[gyro]

Hi guys, I have a few questions regarding charging Lipo batteries. I will be using a 3S 2200mAh 30C battery as the model. If a manufacture states that a battery could be charged up to 3C does that mean a charger could be set the following ways on 3S?
1C - 2.2A
2C - 4.4A
3C - 6.6A
Next, if using a parallel charging board will the batteries all need to have the same mAh, cell count, and C discharge variables? So if you have a two 3S 2200mAh 30C charging; you would not want to put a 3S 1800mAh 20C on the charging board with those? I just want to have a better understanding on this .

Thanks,
Rich B

Rich,

Yes, a 3C charge of a 2200 would be 6.6 amps.

For parallel charging, I believe the biggest rule is having the same cell count, and same battery type/c rating. I think it's ok to have different capacities as long as the batts match otherwise... So your example above would be correct.

 

[Rich B]

Okay, appreciate the help.

Rich

 

[3dNater]

You are fine to charge batteries of different charging C rating so long as you charge them at the lowest rating in the bunch.

Also, when you set your charger you do it based on the total capacity you are charging. In your example if you had 2 packs you would base your C rating on 4400 mah instead of 2200. 4.4 amps would be 1c.

 

[Rich B]

You are fine to charge batteries of different charging C rating so long as you charge them at the lowest rating in the bunch.

Also, when you set your charger you do it based on the total capacity you are charging. In your example if you had 2 packs you would base your C rating on 4400 mah instead of 2200. 4.4 amps would be 1c.

Okay, that makes sense. Thank you.

 

[Dr. Gonzo]

I have been looking at upgrading my charger and start parallel charging. All of the above is true. My quick take is:
1. All the same cell count.
2. Capacity and c-rating mean nothing. You must however charge withing the range of you lowest capacity/C rated pack when setting amperage.
3.Voltage must be similar when CONNECTING BALANCE TAPS. If not you can burn your balance tap wires off as the packs will equalize. To avoid this check cell voltages. If they are not within .25 v you can connect the MAIN leads first for about 30 seconds to let the packs equal out. Then connect your balance taps.
3. Some chargers ask for amps per pack and number of packs and calculate amperage for you be aware of this when getting a new charger.
4. Saftey! Never leave your packs. I have a metal tool cart (more like a table) I use as a charge station and put it in the middle of the garage just incase my mind wanders while outside.
Hope this helps a bit.

 

[gyro]

I have been looking at upgrading my charger and start parallel charging. All of the above is true. My quick take is:
1. All the same cell count.
2. Capacity and c-rating mean nothing. You must however charge withing the range of you lowest capacity/C rated pack when setting amperage.
3.Voltage must be similar when CONNECTING BALANCE TAPS. If not you can burn your balance tap wires off as the packs will equalize. To avoid this check cell voltages. If they are not within .25 v you can connect the MAIN leads first for about 30 seconds to let the packs equal out. Then connect your balance taps.
3. Some chargers ask for amps per pack and number of packs and calculate amperage for you be aware of this when getting a new charger.
4. Saftey! Never leave your packs. I have a metal tool cart (more like a table) I use as a charge station and put it in the middle of the garage just incase my mind wanders while outside.
Hope this helps a bit.

Awesome pointers Mike, thank you!

 

[Rich B]

I have been looking at upgrading my charger and start parallel charging. All of the above is true. My quick take is:
1. All the same cell count.
2. Capacity and c-rating mean nothing. You must however charge withing the range of you lowest capacity/C rated pack when setting amperage.
3.Voltage must be similar when CONNECTING BALANCE TAPS. If not you can burn your balance tap wires off as the packs will equalize. To avoid this check cell voltages. If they are not within .25 v you can connect the MAIN leads first for about 30 seconds to let the packs equal out. Then connect your balance taps.
3. Some chargers ask for amps per pack and number of packs and calculate amperage for you be aware of this when getting a new charger.
4. Saftey! Never leave your packs. I have a metal tool cart (more like a table) I use as a charge station and put it in the middle of the garage just incase my mind wanders while outside.
Hope this helps a bit.

So let me see if I have an understanding on this.

1. 1s-6s batteries for my charger using a parallel board. All like batteries will charge only with their cell count... 1s with other 1s, can not mix 1s with same 2s, etc.
2. Charging say 3s batteries in my case I have friends that will have 1800's thru 2600's. I only have 2200's. So I would set the charger amperage to 1800 times the number of batteries being charge for a 1C charge.
3. Lets same ending voltage after flying reads 3.75 on the lowest battery that will be charged, so if all the batteries are not with in that of .25 volts you must hook the power connectors from the batteries to the board for 30 seconds, then plug in the balancing ports and charge.

Appreciate the information!

Rich

 

[3dNater]

Im not sure you are catching the capacity part quite right. It sounded like you mean that if you have an 1800 and a 2200 you would set the charger for 3.6 amps (1800 x 2) for 1c. You won't hurt anything doing that but you will be charging at less than 1c so it will take more time to charge than you think it should. What you actually do is add all of the different capacities together.

So say you have

800 mah 3s x2
1800 mah 3s
2200 mah 3s

Total capacity is 5600 mah so 1c is 5.6 amps.

 

[Rich B]

Indeed, I misunderstood that part. Thank you for the clarification; I greatly appreciate the help.

Rich