Which is true?

hai every one,

Through out the forum everyone is saying temperature rise will cause series problem to battery (like reduction of battery life ,sulfation etc)

but when i came across this link

http://batteryuniversity.com/learn/article/rising_internal_resistance

it describes

"Sulfation and grid corrosion are the main contributor to the rise of the internal resistance. Temperature also affects the resistance; heat lowers it and cold raises it. Heating the battery will momentarily lower the internal resistance to provide extra run time".


please help me to understand better

Comments

  • vtmaps
    vtmaps Solar Expert Posts: 3,741 ✭✭✭✭
    Re: Which is true?
    11JAGAN wrote: »
    Temperature also affects the resistance; heat lowers it and cold raises it. Heating the battery will momentarily lower the internal resistance to provide extra run time

    please help me to understand better

    Raising battery temp does increase capacity, but at a cost... faster chemical reactions that age the battery sooner.

    Likewise, a cold battery has reduced capacity and higher resistance. A cold battery will age slower, and a battery in storage will benefit from being cold.

    If you are using (cycling) a cold battery, its a bit more complicated. Suppose you have a 100 ah battery (at room temp) and your daily discharge is 20 ah, taking you down to 80% SOC. You will get a certain number of cycles in the life of that battery. Now suppose the battery is cold and has a reduced capacity of 80 ah. If you draw the same 20 ah every day, you are drawing it down to 75% SOC and it will have fewer cycles in its life because you are drawing down to a lower SOC.

    --vtMaps
    4 X 235watt Samsung, Midnite ePanel, Outback VFX3524 FM60 & mate, 4 Interstate L16, trimetric, Honda eu2000i
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: Which is true?

    What is more if you take current from a battery or put current to a battery it is no longer cold because the current flow creates internal heat. So the cold battery starts out with a reduced Amp hour capacity, which then rises as the demand for current warms up the battery. Thus you have the complicated scenario of the battery capacity being reduced for being cold but increasing because of being warmed while also decreasing due to the load demand. Good luck trying to figure out the exact numbers.

    Hence the repeated advice about trying to keep battery temperature as stable as possible by protecting it from both heat gain and heat loss. Also not easy to achieve. But if you can keep the ambient temperature around the batteries at 20C/68F it will be as good as you can hope for.