Good answer by davidgo, and that should be your starting point for understanding and minimizing the issue. But the wording of the question implies that you're thinking about this in a slightly wrong way, and I'll focus on that aspect.
You keep referring to Ubuntu "decreasing" battery life, and that's not really an appropriate way to look at it. Say one OS is better than another at optimizing battery life. If you use the better one as a baseline, the other OS won't be as good in that respect, so it kinda looks like battery life is "decreased" in relative terms.
But really, "batteries decrease battery life". When batteries are a source of power, any battery is a disposable item. Everything you do or don't do affects battery life a little. davidgo's answer lists the major factors.
If one OS uses a little more power than another, that might lead to recharging more often. So some factors can affect other factors. But if you get the daily run time you need even with the OS that uses more power, you might recharge at the same frequency and from a discharge level that, for practical purposes, is in the same range. So your usage pattern may be a bigger factor than the OS.
The point is that batteries have a finite life. There are things you can do to optimize and extend the life a little. To the extent it's practical to do those things, they can't hurt. But finite battery life is a characteristic of operating from batteries. In the scheme of things, a few months difference in battery life doesn't represent a big cost. It doesn't make sense to let it drive important decisions.
Let's assume one OS is not as good as the other at optimizing battery life so it costs you a little more over time for battery replacement. You own the computer because it is a tool to help you accomplish things important to you. People spend extra money to get a keyboard or mouse that they can use more efficiently, or a high-resolution monitor so they can see more of their work at once. The same applies to the OS.
You pick an OS because of what it allows you to do, and things like the user interface that make it easier for you to get your work done. You don't pick it because one will save you a few dollars every couple of years on battery replacement. For that matter, if you are comparing Windows and Ubuntu, Windows costs money and Ubuntu is free. So if Windows saves you a few dollars on battery replacement, you haven't saved money, you paid for that in advance.
Ubuntu doesn't "reduce" battery life. It might yield a slightly different life. But as they say, "that's life".
4
I think a more reasonable cause of batery degradation would be related to the fourth topic (Don’t leave your laptop on permanent charge) in this article: link.
– Ronaldo – 2019-07-30T17:55:01.36717I downvoted because you are ignoring what people write and repeat your question all over the place. – Nobody – 2019-07-30T18:29:32.277
8@nobody And I upvoted because the actual answer is a nuanced, and its valuable to the community! (I also disagree with both you and GabrielaGarcia - and Ive done a significant amount of testing and research here.) – davidgo – 2019-07-30T20:15:57.467
3@Nobody I am not repeating my question .That question was related to dual boot , here i am just asking about ubuntu .If on that place would have edited my question after i accepted the answer then it would have been unfair .Also i am not asking this question just for self benefit since my battery is already dead.It will help others too .Also you can see the answer provided by davidgo is different from the answers provided on the link .Hence my question is bit different . – None – 2019-07-31T04:22:28.933
26Using the battery decreases the battery life. – n0rd – 2019-07-31T09:46:44.117
What is the normal life of a battery? 2-4 years? 40 minutes seems reasonable (you did not mention the total length of time). – Salman A – 2019-07-31T13:40:16.060
1@PeterMortensen 17.10 – None – 2019-07-31T14:34:22.110
2if you are so worried about battery wear then run your laptop on power save mode, unplug it at 80% and plug it at 30% for its entire life. – user14001 – 2019-07-31T15:16:35.397
Are you using the laptop differently when booted into Ubuntu then when booted into Windows? If so, the things you think you observed is not happening. – Jan Doggen – 2019-08-01T13:06:43.317
What does I dual-booted my laptop with Ubuntu 17.10 and Windows 10 one year back mean? You either use Win or Ubuntu.... What are you comparing to what? – Jan Doggen – 2019-08-01T13:08:09.410
Also temperature reduces battery life, if you really want to preserve battery and extend its shelf life you should store it charged (how much charge depends on type) in cold place but not freezer... – Sampo Sarrala - codidact.org – 2019-08-01T17:20:28.757