All about batteries

[Guest]

Here is a great source for battery basics: http://batteryuniversity.com/learn/

 

And here is a good explanation on how to connect batteries: http://www.smartgauge.co.uk/batt_con.html

[Guest]

And here is the best way, connecting using busbars: 

Or like this, but remember, the shorter the cable runs, the better!

[Guest]

Another good article: http://duckworksmagazine.com/11/howto/charging/index.htm

[jacobez]

On 2016/01/14 at 10:39 PM, The Terrible Triplett said:

And here is a good explanation on how to connect batteries: http://www.smartgauge.co.uk/batt_con.html

That is very useful link.

[Guest]

Calculate your required Trojan batteries here: http://www.batterysizingcalculator.com/

[viceroy]

Do you have any information on charging batteries.

Specifically in high heat environments.

I'm asking specifically because my batteries are in the garage which has a mean temperature of 30C, even with ventilation.

The batteries I have have an optimal temp range of 20C to 25C where the bulk charge voltage per cell is 2.35V, and the float charge voltage is 2.25V

In the battery specs, its stated that at 30C, the float charge voltage should be 2.23V, which is fine, I've made that adjustment, but no mention is made of the bulk charge voltage other than it should be 2.35V @ 20C to 25C.

My question is, should I also adjust down the bulk charge voltage to about 2.31V - 2.33V due to the high ambient temps or do they stay at 2.35V?

[Guest]

Nope, bar that I know that heat and batteries should be kept apart, and that you have wisely done what you could ito settings. 

BEST suggestion I can make: Ask your battery supplier for confirmation for if the batteries need to go back under warranty, they may ask a few questions.

[viceroy]

Well after asking the question, I found something on Battery university which mentions adjusting both the float and bulk values so I will keep my settings as is.

 

 

[Chris Hobson]

At 30^oC your gassing Voltage is 2.365 V per cell so you seem under that limit.

 

[superdiy]

Batteries do not like heat, because the reactions inside occur at a higher rate. High temperatures effectively reduces the battery life. You also have to adjust the voltages according to temperatures - refer to your batteries' data sheet - usually you have to reduce the voltage per °C above 25°C.

From the Trojan T105-RE datasheet:

CHARGING TEMPERATURE COMPENSATION
To the Voltage Reading -- Subtract 0.005 volt per cell (VPC) for every 1°C above 25°C or add 0.005 volt per cell for every 1°C below 25°C.

EXPECTED LIFE VS. TEMPERATURE
Chemical reactions internal to the battery are driven by voltage and temperature. The higher the battery temperature, the faster chemical reactions will
occur. While higher temperatures can provide improved discharge performance the increased rate of chemical reactions will result in a corresponding loss of
battery life. As a rule of thumb, for every 10°C increase in temperature the reaction rate doubles. Thus, a month of operation at 35°C is equivalent in battery
life to two months at 25°C. Heat is an enemy of all lead acid batteries, FLA, AGM and gel alike and even small increases in temperature will have a major
influence on battery life.