3LikesLipo Battery Question (Safety)
05-12-2017, 01:24 PM
#16
Lot's of great information here 
.
I will be honest, I am much less concerned about the longevity of the pack and much more concerned about the safety proper storage brings/does not bring. I would love to have my packs last as long as possible but leaving my house with a peace of mind was what drove me to make this post.
Thank you to all for the loads of information and different perspectives.
.I will be honest, I am much less concerned about the longevity of the pack and much more concerned about the safety proper storage brings/does not bring. I would love to have my packs last as long as possible but leaving my house with a peace of mind was what drove me to make this post.
Thank you to all for the loads of information and different perspectives.
05-12-2017, 04:48 PM
#18
Hello!
I think that below you will find some important parameters for safe use of lipo battery.
Charging process and parameters
- Standard Lipo battery parameters
Nominal voltage 3.7 V/cell
Max charge voltage 4.2 V/cell
Storage voltage 3.8 V/cell
Allowable fast charge <= 1C
Min. Discarge voltage 3.0-3.3 V/cell
Example: Charging parameters for Turnigy Nano-tech 2S2P 4200mAh battery and Accucell S60 AC charger
Lipo balance charge:
- current value 4.2A (calculate 1C X 4200mA = 4.2A)
- voltage 7.4V (calculate 2 cells X 3.7V/cell nominal voltage = 7.4V)
- number of cells 2S (I have actualy 4 cells but they are paralell wired...so at the end the setup is 2S)...basicly it is the same setup like for 2S1P type of battery
Safety settings:
- end or final voltage is 8.4V 2S (calculate max charge voltage 4.2V/cell X 2 cells = 8.4V)
- safety timer...how can I calculate the right time of charging? - 1hr should be a sufficient time to charge a 4.2A lipo.
- capacity cut-off...this is basicly the battery capacity so the setup will be 4200mAh
- other defautl settings: temp Cut-Off 50°C, temperature unit Celsius, rest time CHG>DCHG 10min
Lipo storage mode:
- current value 4.2A
- voltage will be in that case 7.6V 2S (calculate storage voltage 3.8V/cell X 2 cells)
Battery protection durning use:
- ESC voltage cut off...available setup on program card hobby king 60A are: 3.0 3.2 and 3.4V/cell - 3.4V per cell is the recommendation.
I am storage the lipo battery in Fire Retardant LiPoly Battery Bag.
I think that below you will find some important parameters for safe use of lipo battery.
Charging process and parameters
- Standard Lipo battery parameters
Nominal voltage 3.7 V/cell
Max charge voltage 4.2 V/cell
Storage voltage 3.8 V/cell
Allowable fast charge <= 1C
Min. Discarge voltage 3.0-3.3 V/cell
Example: Charging parameters for Turnigy Nano-tech 2S2P 4200mAh battery and Accucell S60 AC charger
Lipo balance charge:
- current value 4.2A (calculate 1C X 4200mA = 4.2A)
- voltage 7.4V (calculate 2 cells X 3.7V/cell nominal voltage = 7.4V)
- number of cells 2S (I have actualy 4 cells but they are paralell wired...so at the end the setup is 2S)...basicly it is the same setup like for 2S1P type of battery
Safety settings:
- end or final voltage is 8.4V 2S (calculate max charge voltage 4.2V/cell X 2 cells = 8.4V)
- safety timer...how can I calculate the right time of charging? - 1hr should be a sufficient time to charge a 4.2A lipo.
- capacity cut-off...this is basicly the battery capacity so the setup will be 4200mAh
- other defautl settings: temp Cut-Off 50°C, temperature unit Celsius, rest time CHG>DCHG 10min
Lipo storage mode:
- current value 4.2A
- voltage will be in that case 7.6V 2S (calculate storage voltage 3.8V/cell X 2 cells)
Battery protection durning use:
- ESC voltage cut off...available setup on program card hobby king 60A are: 3.0 3.2 and 3.4V/cell - 3.4V per cell is the recommendation.
I am storage the lipo battery in Fire Retardant LiPoly Battery Bag.
09-12-2023, 07:14 AM
#19
Tech Rookie
Read this article on how to store em
I was looking around the web because i have the same issue i have a extremely puffed dynamite lipo battery 2 cell and the case has already popped off of it and i found this article on the best practices for storing lipo batterys. It says that you should discharge halfway and maintain a certain voltage and keep it in normal temperatures and isolate it away from stuff that can catch fire.and it also says that one of the best ways to safely store is to get a lipo safe. https://grantselectronics.com/2023/09/11/best-practices-for-storing-lipo-batteries-safely/
09-12-2023, 09:16 AM
#20
Do you guys really keep all your packs at 3.8v all of the time? What do you do when you realize you want to run your car for a few minutes? First you have to charge your packs, which takes ~45min at 1C, and of course you only charge at 1C...
A more pragmatic view about batteries:
Batteries are good for a limited number of charge/discharge cycles. Even with the most tender loving care, they will degrade just because you charge them. And the discharge rate of most RC applications is high enough to accelerate the degradation of a battery, dramatically reducing the number of charge/discharge cycles. If we made a pie chart of the causes of degradation of a battery, discharge rate will account for probably 90% of performance lose.
All of the other factors being mentioned here will account for the remaining 10%.
To protect your batteries while enjoying the hobby, be careful you do not over-discharge, either at too many amps or down to too low of a voltage. And do not charge above the recommend 4.2v. Random failure can still happen due to a defect, but it is extremely rare.
I do store my packs in an ammo can just to be safe.
Overall I believe this hobby should be about having fun. So I keep my batteries charged, so they are ready at a moments notice. I charge my batteries at 1C at the end of the day, but if I'm at a track, my priority is to keep running! That's the point of this whole thing, right? I try to keep 3 batteries for a car, which will let me run almost continuously! And I'll probably be charging at 2C, maybe even 3C. Whatever it takes to keep the wheels spinnin'.
And my batteries have held up just fine. My first packs I ever bought are still performing well!
A more pragmatic view about batteries:
Batteries are good for a limited number of charge/discharge cycles. Even with the most tender loving care, they will degrade just because you charge them. And the discharge rate of most RC applications is high enough to accelerate the degradation of a battery, dramatically reducing the number of charge/discharge cycles. If we made a pie chart of the causes of degradation of a battery, discharge rate will account for probably 90% of performance lose.
All of the other factors being mentioned here will account for the remaining 10%.
To protect your batteries while enjoying the hobby, be careful you do not over-discharge, either at too many amps or down to too low of a voltage. And do not charge above the recommend 4.2v. Random failure can still happen due to a defect, but it is extremely rare.
I do store my packs in an ammo can just to be safe.
Overall I believe this hobby should be about having fun. So I keep my batteries charged, so they are ready at a moments notice. I charge my batteries at 1C at the end of the day, but if I'm at a track, my priority is to keep running! That's the point of this whole thing, right? I try to keep 3 batteries for a car, which will let me run almost continuously! And I'll probably be charging at 2C, maybe even 3C. Whatever it takes to keep the wheels spinnin'.
And my batteries have held up just fine. My first packs I ever bought are still performing well!
My weaker old race packs become fun practice batteries. To be charged harshly. Only my newest race packs get the full on religious discharge to storage treatment everytime. If you put them away at 4.0-4.1v, thats fine.
1c? Lol. I charge race packs at 40 amps. Motor temp limits my down time, not battery charging. I try a few setup changes while the motor cools. The battery will be fully cycled long before that.
Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
