power tools battery life

Old 12-08-19, 01:46 PM
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power tools battery life

Do all power tool batteries die in about the same amount of time, or does a certain brand's last noticeably longer because it has better charging and maintenance technology?

I'm not talking about run-time (how long you can use the tool before needing to recharge. I mean how long it last before you need to get a new battery (measured in years).
Old 12-08-19, 02:08 PM
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I suspect this will be a difficult question to answer without a lot of comparison as there are many aspects to battery selection including battery type and voltage.

However, let me rephrase your question because the real issue - for quality batteries - is cycle life. Cycle life refers to the number of times a battery can be used before it can no longer hold an adequate charge. So, if a battery has a cycle life of 500 charges and you use it daily it can last close to two years but if you use it weekly it can last close to 10 years, or monthly about 40 years.

Also, you don't want to consider run time, known as capacity, but it's still important. After all if you worked for 500 hours straight, a battery with a 1 hour theoretical capacity and 500 cycle life charges would last as long as a battery with a 500 hour capacity and a 1 cycle life - in theory.

As a side note, a Tesla is claimed to operate for 6,000 cycles at 200 miles per cycle (run time) or 1.2 million miles.

Last edited by Tony P.; 12-08-19 at 02:59 PM.
Old 12-08-19, 02:23 PM
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And, I think...... I think, Ryobi says leave their 18v batteries on the charger all the time. We started buying those cordless tools about 4 years ago. We bought a trimmer (weedeater thingy) and we've had no issues. Bought a blower shortly after that.
We bought about 6 or 8 tools throughout the last 4 years & no issues from any of the batteries. We have a pole saw, sander, calk gun etc.

Having said that, I dont know about other tools.
Old 12-08-19, 04:00 PM
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You must beat the hell out of the batteries. You MUST use them routinely. Charging them and then letting them sit around will kill them. I have batteries that are very old but I cycle my batteries in order and then use them routinely.

Batteries cannot be left on the charger.

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