4ah battery charged in 30 minutes

Lord Muzzy

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Mar 28, 2014
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94
Hi, can someone explain why my Makita L-ion 4ah battery (which I presume is a bunch of 18650's or something similar?) can charge in just half an hour? Why can't we charge our flashlight 18650's in such short times??

Sorry if this has been explained before.
 

HKJ

Flashaholic
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Mar 26, 2008
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Copenhagen, Denmark
High current batteries can often be charged fast, the charge may not be to 100% but maybe only 95% and it will wear the battery down faster. Neither of these caveats may have any significance in real life.
The batteries used are usual low capacity, but high current batteries. Use the same type in your flashlight and find a charger that will do fast charge and you are there.
 

peter yetman

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Mar 23, 2014
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North Norfolk UK
UNless you have a charger that charges at 8 amps - which is very unlikely and dangerous - you cell was either charged already or you are wrong.
Have you checked the cell with a DMM?
Most reputable chergers charge Li-ions at 1 or 2 amps, beware.
P
 

alpg88

Flashlight Enthusiast
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Apr 19, 2005
Messages
5,283
yea, it is dangerous unless you take precautions, it is no accident that battery packs have build in thermal sensors, and chargers have fans that blow air thru the pack around each cells while charging.
 

alpg88

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Apr 19, 2005
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5,283
there is a cc\cv board sold on ebay, amazon. etc. about 5 bucks, it works as buck driver, charger, and voltage regulator, it can be set to charge with current higher than 1-2A.
 

Nev

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Mar 25, 2017
Messages
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I have a dewalt fast charger that charges 2-3 AH battery's in 15 mins , but for nicad & nimh.
 

AVService

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Dec 30, 2011
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2,163
The battery packs for power tools are a closed system designed to work with the charger for quick reuse of the batteries in the tool.

Much higher Voltage and Current Capacity than what we typically use in a light and thus can be more safely charged more quickly too.

Not sure exactly what you are asking but most of us charge flashlight batteries by themselves and not as a pack and at a slow and safe rate for the capacity which is a fraction of that for a tool battery pack.

The Makita packs have circuitry in them too to work as part of their system.

The batteries for our lights are charged as fast as they can be safely and considering the fairly wide range of cells likely to be seen by hobbyist chargers they are made to charge safe & slow instead of quickly for the batteries they can not know for sure about that we charge.
 

sbj

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Feb 19, 2017
Messages
172
I also have a Makita charger (DC18RA) that charges a 3Ah battery in 20 minutes. If this indicates "full", however, the cells are only charged to 4.0V. This corresponds to approx. 80% capacity compared to 4.20V. The capacity printed on the battery 3.0Ah (there are 10 pieces of 1500mAh cells installed), so can not be achieved. Nevertheless, I am very satisfied with the performance and endurance of the drill and the battery.
When I'm not in time trouble, I charge my tool batteries a little slower with a hobbycharger.
You can measure the voltage of your battery pack after charging. It is probably also at about only 20.0 volts.
 
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