electrical battery randomly goes dead more when cold

I've been a mack truck tech for 30 years we have a 2800.00 bat and alt tester I believe I'm looking for a factory flaw or something

If it was a factory flaw, it would have shown up a lot sooner then now, it's 13 years old. As a mechanic you should know this. I have a tester that can allow me to change the ambient temperature setting, and it is pretty dead on in finding load test at different ambient temperature settings to ensure how the temp will effect the quality of the battery, starter, and the alternator. You're missing something but I'm sure if you step back and think, you will figure it out, we can help, that's why you're here.

the car came from okla. about a year ago has been to the dealer several time befor I got it they couldn't find anything note even in hot summer days I can stop at a store for 15 minuts and it will hardly start this may happen once in a month in deep cold every morning have to jump it starter sounds probable but for 150.00+ I would like to be more sure thanks

Check the resistance in the grounds, battery to engine and straps. Weather and heat could be a cause for a grounding issue, just a comment.

That's why when it's 10 deg it won't start let get 70 deg and it works. Huh. I guess at 70 deg. Put it in the freezer then take it out and try it. Not

I am going to try to help you with your thoughts, the battery is one part of the system, it is a storage container, cold weather keeps electrons stored nicely, those electrons get really close together. battery is loving life. now for a vehicles engine to crank, those electrons have got to move, they have to get going thru the battery cables to that starter, this is where the cold weather affects an engine starting. those electrons hate to move during cold weather, the colder it is, the slower they move. do you understand how that works now.

Oh I understand how they work and know they don't do their job in the cold and don't need you to school anybody except your kids and DIY'ers don't have a clue of what your trying to say. So answer some of your own questions instead of commenting on other answers so we can critique your answers like basketball analogy you used with a stupid answer.

you cannot admit to being wrong ?

I know what works and what doesn't and also not to waste words on theory and practical application on a site fied with people wanting to know which part is going to fix their car in a world of diagnostics. Practical information of the ins and outs of advice. If you want to be above the level of help go join the engineers and talk about the other parts of design but here be practical with people who just want some advice.

much better ProfessorG, didn't mean to step on your contribution, have read a lot of your replies to people and you have given very good advice. I will refrain from making a small correction to anything you have responded to future wise.

keep cool guys all answers are good and helpful I have to say one guy said 13 years old means factory flaws are over not true I just replaced a fuel pump new pump comes with an updated plug to prevent fire another is the abs module still bad to this day anyway more history on the blazer before I got it it was wrecked front and rear then repaired this thing is like new undercarriage no rust the long fuel tank strap stud once I took the tension off I unscrewed it with my fingers even the rad clamps are clean I believe there is an intermittent draw on the battery and the cold just makes it worse I drove it for the last 2 days 30 and 40 degrees no problem at all i'll have to wait till it doesn't start then test for draw ect. because any other time it test ok this car came from my sister they had everything done at their dealer they even have nitrogen in the tires but never found this problem I do thank you all for your feedback and will continue to watch ps the dealer disconnected the onstar witch I know nothing about

Onstar went to digital and most 05 or newer will only work, 05 if you update it. Good luck.