Dewalt 20v batteries come in different capacities. The total amp-hours decide how long it will last in a single charge.
Following is the list of Dewalt 20v Lithium-Ion Batteries:
- 20V MAX 1.5Ah Compact Battery (DCB201)
- 20V MAX 1.7 Ah DEWALT POWERSTACK™ Compact Battery (DCBP034-2)
- 20V MAX 2.0Ah Battery (DCB203G/DCB203/DCB203BT)
- 20V MAX 3Ah Battery (DCB200/DCB230-2)
- 20V MAX 4Ah Lithium Ion Battery Pack (DCB204/DCB240-2)
- 20V MAX 5Ah Battery (DCB205/DCB205G/DCB205BTLR/DCB205-2)
- 20V MAX 6Ah Battery (DCB206-2/DCB606)
- 20V MAX 8Ah Battery (DCB208)
- 20V/60V MAX 9.0Ah Battery (DCB609)
- 20V MAX 10.0Ah Lithium Ion Battery (DCB210)
But the question is…
FOR WHAT TASK do you need the runtime?
Many factors affect the total run-time for Dewalt 20v Batteries. Therefore, I have selected a medium-duty task of driving 1½-inch #10 wood screws into a common pine to find how long a single battery will last on a single charge.
How Long Do Dewalt 20v Batteries Last?
A Dewalt 20v 1.5Ah battery can last a continuous 27 mins for medium to heavy-duty tasks, like driving 1½-inch #10 wood screws into common pine.
A Dewalt 20v 1.7Ah PowerStack battery can last a continuous 39 mins for medium to heavy-duty tasks, like driving 1½-inch #10 wood screws into common pine.
A Dewalt 2.0Ah battery can last a continuous 43 Mins for medium to heavy-duty tasks, like driving 1½-inch #10 wood screws into common pine.
A Dewalt 3.0Ah battery can last a continuous 56 Mins for medium to heavy-duty tasks, like driving 1½-inch #10 wood screws into common pine.
A Dewalt 4.0Ah battery can last a continuous 1 Hour 19 Mins for medium to heavy-duty tasks, like driving 1½-inch #10 wood screws into common pine.
A Dewalt 5.0Ah battery can last a continuous 1 Hour 39 Mins for medium to heavy-duty tasks, like driving 1½-inch #10 wood screws into common pine.
A Dewalt 6.0Ah battery can last a continuous 2 Hour 06 Mins for medium to heavy-duty tasks, like driving 1½-inch #10 wood screws into common pine.
A Dewalt 8.0Ah battery can last a continuous 2 Hour 38 Mins for medium to heavy-duty tasks, like driving 1½-inch #10 wood screws into common pine.
A Dewalt 9.0Ah battery can last a continuous 3 Hour 08 Mins for medium to heavy-duty tasks, like driving 1½-inch #10 wood screws into common pine.
A Dewalt 10.0Ah battery can last a continuous 3 Hour 31 Mins for medium to heavy-duty tasks, like driving 1½-inch #10 wood screws into common pine.
| Dewalt Battery | Dewalt Drill | Screw Size | Material | Runtime | Total Screws |
|---|---|---|---|---|---|
| 20V 1.5Ah | 1/2″ Brushless | 1½-inch #10 wood screws | Common Pine Wood | 27 mins | 207 |
| 20V 1.7Ah | 1/2″ Brushless | 1½-inch #10 wood screws | Common Pine Wood | 39 mins | 243 |
| 20V 2.0Ah | 1/2″ Brushless | 1½-inch #10 wood screws | Common Pine Wood | 43 mins | 267 |
| 20V 3.0Ah | 1/2″ Brushless | 1½-inch #10 wood screws | Common Pine Wood | 56 mins | 405 |
| 20V 4.0Ah | 1/2″ Brushless | 1½-inch #10 wood screws | Common Pine Wood | 1 Hour 19 mins | 438 |
| 20V 5.0Ah | 1/2″ Brushless | 1½-inch #10 wood screws | Common Pine Wood | 1 Hour 39 mins | 684 |
| 20V 6.0Ah | 1/2″ Brushless | 1½-inch #10 wood screws | Common Pine Wood | 2 Hour 06 mins | 826 |
| 20V 8.0Ah | 1/2″ Brushless | 1½-inch #10 wood screws | Common Pine Wood | 2 Hour 38 mins | 1109 |
| 20V 9.0Ah | 1/2″ Brushless | 1½-inch #10 wood screws | Common Pine Wood | 3 Hour 08 mins | 1230 |
| 20V 10Ah | 1/2″ Brushless | 1½-inch #10 wood screws | Common Pine Wood | 3 Hour 31 mins | 1367 |
Factors Affecting Total Runtime of Dewalt 20V Battery
The total runtime of a Dewalt 20V battery largely depends on multiple factors and can vary from one situation to another.
Battery Size of Dewalt 20V Battery:
The first thing which affects the overall runtime of a Dewalt 20V battery is the amp hours. Amp hours is the amount of continuous current a battery can provide for one hour.
Current then translates into the amount of power a battery can deliver.
Power Output = Voltage x Amp-Hour
Below is a chart for how many watts a Dewalt 20V battery can provide for a fixed duration before it runs out of charge.
These are theoretical numbers. The actual figures will be 10%-15% lower. The overall capacity will drop 20% after 300-600 cycles of usage.
| Dewalt 20V Battery | Power Output (1 Hour) | Power Output (30 Mins) | Power Output (15 Mins) |
|---|---|---|---|
| 20V 1.5Ah | 30 Watts | 60 Watts | 120 Watts |
| 20V 2.0Ah | 40 Watts | 80 Watts | 160 Watts |
| 20V 3.0Ah | 60 Watts | 120 Watts | 240 Watts |
| 20V 4.0Ah | 80 Watts | 160 Watts | 320 Watts |
| 20V 5.0Ah | 100 Watts | 200 Watts | 400 Watts |
| 20V 6.0Ah | 120 Watts | 240 Watts | 480 Watts |
| 20V 8.0Ah | 160 Watts | 320 Watts | 620 Watts |
| 20V 9.0Ah | 180 Watts | 360 Watts | 720 Watts |
| 20V 10.0Ah | 200 Watts | 400 Watts | 800 Watts |
Type of Work You Are Using Yous Dewalt 20V Battery For:
As explained in the last heading, the overall run-time of a Dewalt 20V battery largely depends on what task you are doing.
For example, drilling in concrete will yield low runtimes, while driving screws in softwood will give phenomenal runtimes.
Similarly, a circular saw cutting a soft wooden board will yield different results than a hard oak wood block.
The run-time is directly proportional to usage and power output. Below is a very rough comparison.
| Dewalt 20V Battery | Task | Material | Runtime |
|---|---|---|---|
| 20V 5.0Ah | Drilling | Soft Wood | 70-90 Mins |
| 20V 5.0Ah | Drilling | Hard Wood | 50-60 Mins |
| 20V 5.0Ah | Drilling | Concrete | 30-40 Mins |
Operating Temperature of Dewalt 20V Battery:
The total runtime of a 20V Dewalt lithium-ion battery highly depends on the battery temperature. The temperature of the battery also affects the battery’s overall cycles.
Dewalt 20V batteries come with a temperature sensor. As soon as the temperature reaches a set threshold, a Dewalt tool will stop working to avoid damage to your 20V HART battery.
Run-Cycles Vs. The runtime of Dewalt 20V Battery:
The overall run time of a Lithium-Ion Dewalt 20V battery drops as it ages. Following is a chart describing the runtime of a 2oV 2 Amp Hour Battery after a certain number of run cycles.
Brushed vs. Brushless Motor:
Brushless motors are a lot more energy efficient than brushless motors. The energy efficiency comes due to the absence of physical brush contacts present in brushed motors.
The contacts produce a lot of heat and waste energy. So, the overall runtime of a Dewalt 20V battery dramatically depends on the type of motor used in your tool.
BRUSHLESS motors do NOT power all Dewalt tools, so the runtime can be slightly lower for non-brushless tools than mentioned above.
Below is a great video to understand the differences between a brushed and brushless motor.
Condition of Your Dewalt Cordless Tool:
A brand new Dewalt tool will run longer than an old one on the same battery. New tools are efficient with minimal friction inside their mechanical components.
The losses inside an old clumsy Dewalt tool will yield lower run times. So make sure your tools are properly lubricated and in good condition before planning to change your batteries.
How Long Will a Dewalt 20V Battery Last in terms of Life Cycle?
Dewalt 20V Batteries are lithium-ion batteries. Dewalt uses high-quality Li-Ion cells, which last longer than low-quality cheap drills, which cost the same as a Ryobi drill Battery with a battery and charger.
Under normal conditions, your drill battery will last 4-6 years or 500-800 cycles. The overall life of your Dewalt battery highly depends on operating temperatures, workload, charging & discharging behavior.
Operating Temperatures:
The overall life cycle of an 20V Dewalt battery highly depends on the operating temperatures.
Below is a graph showing the effect of temperature vs. Life Cycles of a Dewalt 20V Battery.
Charging and Discharging Behaviour:
Ok, so there are a few things you should take care of related to your 18V Lithium-ion Dewalt batteries.
For the best overall life cycle, the best practice is to recharge your battery as soon as your tool starts showing signs of a lower battery.
Don’t wait for your battery to fully discharge before you charge it again to avoid losing life cycles.
Another thing you should take care of is to avoid storing a fully charged or fully discharged battery. This is the biggest reason for destroying your battery life cycle.
Fully charged batteries affect the internal chemistry if kept for a long term, like a few weeks or months.
Similarly, a fully discharged Dewalt 20V battery will keep losing charge and reach a point where the terminal voltage is too low to be detected by a charger.
This will also affect your Dewalt 20V battery’s overall life.
How Long Does it Take to Charge a Dewalt 20V Battery?
Different Dewalt batteries will require different amounts of time to fully charge. The charging time is also dependent on the type of charger being used.
Before I explain how fast a 20V Dewalt battery will charge, let me explain C rating of a Li-Ion battery and how it limits the charging speed.
C rating of a typical Dewalt 20V Li-ion battery is 3-4 for a safe discharge. For charging, a C rating of 1 is considered safe.
C Rating means, the rate at which current is with drawn from your battery pack. If you are discharging a battery at 1C, it means, it will completely drain in 1 Hour.
Similarly, a 2C will drain the battery twice faster, making it to last 30 mins only.
The formula is as under:
Power Output= Voltage x Amp-Hour x C-Rating
Dewalt 2.0Ah Battery: Power Out=20V x 2.0 Ah x 1 = 40 Watts/Hour
The same formula applies for Charging your battery. If we provide 40 Watts to a fully discharge DeWalt 2.0 Ah battery, it will fully charge in 60 mins.
Fast chargers can pump a dramatic continuous 240 Watts into a battery if it does not cross a C rating of 2 at lower voltages and 0.75C near fully charged.
So, despite a fast charger is capable of providing a lot of power, if a battery is small in size, it will withdraw lower power to charge to avoid damaging the battery.
Hence, a dewalt fast charger will take 30-40 mins to charge a 2Ah, 3Ah, 4Ah, and 5 Ah 20V battery. A 6Ah 20V Dewalt battery will take 40-45 mins to charge. A 8Ah, 9Ah and 10Ah battery will take under 90 mins to charge.
Dewalt typical slow chargers will take longer to charge 20V dewalt Batteries. I have summarized the charging period of each dewalt battery availble on market.
| Dewalt 20V Battery | Max Power Input (2C – 0% to 50%) | Fast Charger | Slow Charger |
|---|---|---|---|
| 20V 1.5Ah | 60 Watts | 30-40 Mins | 30-40 Mins |
| 20V 2.0Ah | 80 Watts | 30-40 Mins | 30-40 Mins |
| 20V 3.0Ah | 120 Watts | 30-40 Mins | 40-50 Mins |
| 20V 4.0Ah | 160 Watts | 30-40 Mins | 60-70 Mins |
| 20V 5.0Ah | 200 Watts | 30-40 Mins | 1 Hours 15 Mins |
| 20V 6.0Ah | 240 Watts | 40-45 Mins | 1 Hours 30 Mins |
| 20V 8.0Ah | 320 Watts | 1 Hour 10 Mins | 2 Hours |
| 20V 9.0Ah | 360 Watts | 1 Hour 20 Mins | 2 Hours 15 Mins |
| 20V 10.0Ah | 400 Watts | 1 Hour 30 Mins | 2 Hours 30 Mins |
Additional Read: