How can I tell if its the battery problem or motherboard problem?

[Android Central Question]

I'm using LG G Pro 2 (model f350l) with Li-ion (removable) battery.

The battery drained from 100 to 0 in 2 hours and constantly overheated even without using. The battery is not bloated or swollen.
The phone can be charged and there's no heat while charging. ON/OFF and everything else is working fine.

I often left the phone charging overnight leaving it overcharged. I've read somewhere that lithium battery will stop the charging when the battery is fully charged.

I wanted to get a new battery but am not sure if its the battery that's damage and needs to be replaced or is it a motherboard problem.
How can I tell whether its the battery or motherboard problem?

Appreciate your expert advice.

 

[Mooncatt]

I often left the phone charging overnight leaving it overcharged. I've read somewhere that lithium battery will stop the charging when the battery is fully charged.

All chargers are automatic, so you didn't overcharge the battery. What happened is you were leaving it at a high state of charge, which is above 75%. That, and draining below 30% are the two biggest killers of Li-ion batteries, and the general guideline for phones is to keep it between 40-80% for longer life. I think your battery is probably going bad, not the motherboard.

Appreciate your expert advice.

I'm not an expert, but I did stay at a Holiday Inn once. These guys, on the other hand, are experts.

https://batteryuniversity.com/index.php/learn/article/how_to_prolong_lithium_based_batteries

 

[methodman89]

Also, go to Settings, Battery, and see if anything was using the device.

 

[Rukbat]

Usually charging to 100% is okay, because the charger (the circuit inside the phone - the thing you plug into the wall is just a power supply) stops the charging at 100%, then kicks in if the battery falls below about 98% and tops it off. (If the circuit goes bad, that can cook the electrolyte out of the battery and destroy it.)

If this is the original battery, it's going on 5 years old and almost definitely shot. (Take it out, put it on a flat surface and try to spin it. If it makes even one full turn, it's swollen.) But I've run my batteries between 40% and 90% for years, and never had a problem with longevity. (That's not to say that they never go bad, they do. And 5 years is 2 years of gift.)

One day we'll see better lithium technology - the auto industry is spending billions (that's with a "b") trying to get all the bugs out, because replacing a battery in an electric car, if it's still under warranty, is something no manufacturer ever wants to do (and owners wouldn't be thrilled paying the $5,000 it will cost if it's out of warranty). They 're also working on reducing the weight to power ratio, so some day we may see phones that can go a week between charges.