A highly common kind of power inverters utilized in emergency situations, camping, off-grid applications, medical and security systems, and similar applications is the 3000-watt power inverter.

The majority of 3000-watt power inverters are fairly easy to operate, however problems with runtime and dependability might arise when sizing the necessary batteries or battery packs.

Energy and Power Requirements for 3000 Watt Power Inverters

Power inverters are not perfect devices and experience some energy loss when converting energy.

Although there are units with superior energy efficiency, such units are often more costly ones, good power inverters have an energy efficiency of around 85%.

As a result, assuming the power inverter has a 3000 Watt continuous output, the necessary battery power is:

PBat = PInv / Energy Efficiency % = 3000 Watt / 0.85 = 3530 Watts

Additionally, as power inverters often have a surge output power that is two times as much as the continuous output power, the battery must provide substantially more power for a very little period of time (typically only a few seconds):

PBat = PInt / Energy Efficiency % = 6000 Watt / 0.85 = 7060 Watts

Therefore, the battery (or battery pack) has to be able to provide 3600 watts constantly and 7200 surge watts in order to power a 3000 Watt power inverter with an energy efficiency of 85%.

This addresses the issue of power.

But what about the need for energy?

Power inverters often don’t run continuously at full capacity; if they do, the device is significantly underpowered.

Energy needs are often specified as continuous power for a certain period of time, such as 1000W for 3 hours.

In such instance, the battery’s required energy is determined using the following formulas:

PBat = 1000 W / 0.85 W = 1200 W

EBat = PBat * T (h) = 1200 Watt * 3 hours = 3600 Wh = 3.6 kWh

In this scenario, a battery that can provide 3600 Watts constantly, 7200 surge Watts, and at least 3.6 kWh of energy is required to power a 3000 Watt power inverter with a surge power of 6000 Watt and an energy efficiency of 85%.

There are 3000 Watt power inverters that take 24V, 36V, or even 48V in addition to the more common 12V devices.

Calculating battery currents is simple:

IBatCont = P(W) / U(V) = 3600W / 12V = 300 Amps

IBatSurge = P(W) / U(V) = 7200W / 12V = 600 Amps

IBatAverage = P(W) / U(V) = 1200W / 12V = 100 Amps

Note: Currents are rather significant when powering 3000W inverters with 12V batteries.

The following formula may be used to determine the real capacity of a battery:

Actual Capacity = Required Energy (Wh) / U(V) = 3600 Wh / 12V = 300 Ah

Actual Capacity vs. Nominal Capacity: A battery’s nominal capacity is the amount of energy it can hold after being depleted for 20 hours.

The real capacity of a battery, particularly a lead-acid battery, diminishes as it is depleted more quickly; with lead-acid batteries, the actual capacity after 1 hour might be as low as 50–70% of the nominal capacity after 20 hours.

Lithium deep discharge batteries are less susceptible to capacity loss due to discharge current, however if a particular current is achieved, the lithium battery is disconnected by the integrated Battery Management System (BMS) to prevent overcurrent discharge.

Personally, I believe that lithium batteries are much superior than lead-acid batteries for the majority of applications; for more information on these batteries, feel free to read our post on the Best 12V, 24V, 36V, and 48V Lithium Deep Cycle Battery For a Power Inverter.

One of the top batteries in its class, the Ampere Time 12V 300Ah battery, for instance, supports:

  • 200 Amps maximum continuous current;
  • A maximum 5 second surge current of 400 Amps,
  • The joining of four batteries in parallel and four batteries in series to make bigger battery packs.

In our example, we would want at least two of these batteries linked in parallel to power a 3000W power inverter.

This kind of battery pack would support:

  • Maximum continuous current of 400 Amps, which exceeds the necessary 300 Amps,
  • A maximum surge current of 800 Amps for 5 seconds, which exceeds the necessary 600 Amps,
  • The actual capacity, which is 600 Ah rather than the needed 300 Ah,

If the battery pack is too big, keep in mind that Ampere Time 12V 200Ah battery has the same current constraints but offers a capacity of 400 Ah when two batteries are linked in parallel.

This capacity is still more than adequate for our scenario.

Of course, there are further 12V lithium batteries that can run 3000W and comparable power inverters, such as the following:

ModelBattery Type
Chemistry
Group Size
Capacity (Ah)
Discharge CurrentsParallel / Series ConnectionsWeight (lbs/kg)
Aicipow PDAC-12100Deep Cycle
LiFePO4
31
100
100A cont.P: up to 4
S: up to 4
26 lbs; 11.8 kg
Aicipow PDAC-12200Deep Cycle
LiFePO4
4D (6D)
200
100A cont.P: up to 4
S: up to 4
58 lbs; 26.3 kg
AIMS Power LFP12V50ADeep Cycle
LiFePO4

50
50A cont.
100A 10s
?17.75 lbs; 8.04 kg
AIMS Power LFP12V100ADeep Cycle
LiFePO4
31
100
100A cont.
200A 10s
?30.2 lbs; 13.7 kg
AIMS Power LFP12V200ADeep Cycle
LiFePO4
4D (6D)
200
160A cont.
350A 10s
?77 lbs; 34.9 kg
AIMS Power LFP12V50BDeep Cycle
LiFePO4

50
50A cont.
100A 10s
P: up to 4
S: up to 4
15.5 lbs; 7.0 kg
AIMS Power LFP12V100BDeep Cycle
LiFePO4
31
100
100A cont.
200A 10s
P: up to 4
S: up to 4
28.5 lbs; 12.9 kg
AIMS Power LFP12V200BDeep Cycle
LiFePO4
4D (6D)
200
200A cont.
400A 10s
P: up to 4
S: up to 4
62 lbs; 28.1 kg
Ampere 12V 50Ah PlusDeep Cycle
LiFePO4

50
50A cont.
100A 5s
P: no limits (4?)
S: up to 4
14.3 lbs; 6.5 kg
Ampere 12V 100AhDeep Cycle
LiFePO4
31
100
100A cont.
280A 5s
P: up to 4
S: up to 4
24.25 lbs; 11 kg
Ampere 12V 200Ah PlusDeep Cycle
LiFePO4
4D (6D)
200
200A cont.
400A 5s
P: up to 4
S: up to 4
52.3 lbs; 23.7 kg
Ampere 12V 300Ah PlusDeep Cycle
LiFePO4
4D (8D)
300
200A cont.
400A 5s
P: up to 4
S: up to 4
63 lbs; 28.54 kg
Ampere 12V 400Ah PlusDeep Cycle
LiFePO4
8D
400
250A  cont.
750A 5s
P: up to 4
S: up to 4
86.2 lbs; 39.1 kg
Banshee LFP-31MDual Purpose
LiFePO4
31
100
1200 CCAP: ?
S: up to 4
24.2 lbs; 11 kg
Battle Born BB5012Deep Cycle
LiFePO4

50
60A cont.
100A 30s
P: yes
S: up to 4
17.6 lbs; ~8.0 kg
Battle Born BB10012Deep Cycle
LiFePO4
31
100
100A cont.
200A 30s
P: yes
S: up to 4
29 lbs; 13.2 kg
Battle Born BBGC2Deep Cycle
LiFePO4
GC2
100
100A cont.
200A 30s
P: yes
S: up to 4
31 lbs; 14 kg
Bioenno Power BLF-12100WSDeep Cycle
LiFePO4
31
100
100A cont.
200A 5s
(not recommended)28.1 lbs; 12.8 kg
Chins 12V50AhDeep Cycle
LiFePO4

50
50A cont.
150A 5s
P: up to 4
S: up to 4
13.8 lbs; 6.3 kg
Chins 12V100AhDeep Cycle
LiFePO4
31
100
100A cont.
300A 5s.
P: up to 4
S: up to 4
23.9 lbs; 10.8 kg
Chins 12V200AhDeep Cycle
LiFePO4
4D (6D)
200
200A cont.
600A 5s
P: up to 4
S: up to 4
49.4 lbs; 22.4 kg
Chins 12V300AhDeep Cycle
LiFePO4
4D (6D)
300
200A cont.
600A 5s
P: up to 4
S: up to 4
67.3 lbs; 30.5 kg
Chins 12V400AhDeep Cycle
LiFePO4
4D (6D)
400
250A cont.
750A 5s
P: up to 4
S: up to 4
86.4 lbs; 39.2 kg
Eastup 1250750Dual Purpose
LiFePO4
34R/97R
50
750 CCA
930 MCA
?15.43 lbs; ~7.0 kg
Eastup 12751000Dual Purpose
LiFePO4
94R
75
1000 CCA?18.5 lbs; 8.4 kg
Eco-Worthy 12V50AhDeep Cycle
LiFePO4

50
60A cont.P: unlimited
S: up to 4 
11.9 lbs; 5.4 kg
Eco-Worthy 12V100AhDeep Cycle
LiFePO4
34
100
P: up to 4
S: up to 4
23 lbs; 10.4 kg
Eco-Worthy 12V150AhDeep Cycle
LiFePO4 
31
150
150A cont.P: unlimited
S: up to 4 
36.7 lbs; 16.6 kg
Eco-Worthy 12V200AhDeep Cycle
LiFePO4

200
120A cont.P: unlimited
S: up to 4
52.9 lbs; 24 kg
ExpertPower EP1250Deep Cycle
LiFePO4

50
50A cont.
100A 10s
?13 lbs; 5.9 kg
ExpertPower EP12100Deep Cycle
LiFePO4
31
100
100A cont.
200A 2s
?22.6 lbs; 10.3 kg
ExpertPower EP12200Deep Cycle
LiFePO4
4D (6D)
200
150A cont.
200A 3s
?48.3 lbs; 21.9 kg
GLI GLIBATT12050Deep Cycle
LiFePO4
26
50
50A cont.
500A 5s(?)
P: yes
S: up to 4
12 pounds; 5.5 kg
GreenLiFE GL50-50AHDeep Cycle
LiFePO4
21
50
50A cont.Yes15 lbs; 6.8 kg
GreenLiFE GL80-80AHDeep Cycle
LiFePO4
27
80
80A cont.Yes28 lbs; 12.8 kg
GreenLiFE GL100-100AHDeep Cycle
LiFePO4
31
100
100A cont.
1000A 5s
Yes31 lbs; 14 kg
GreenLiFE GL260-260AHDeep Cycle
LiFePO4
8D
260
100A cont.
2600A 5A
Yes80 lbs; 36.24 kg
JITA 12V100AhDeep Cycle
LiFePO4
31
100
100A cont.P: up to 4
S: up to 4
23.8 lbs; 10.8 kg
JITA 12V200AhDeep Cycle
LiFePO4
4D (6D)
200
200A cont.P: up to 4
S: up to 4
48.9 lbs; 22.2 kg
JITA 12V300AhDeep Cycle
LiFePO4
4D (6D)
300
200A cont.P: up to 4
S: up to 4
59.5 lbs; 27 kg
JITA 12V400AhDeep Cycle
LiFePO4
4D(6D)
400
200A cont.
400A 5s
P: up to 4
S: up to 4
83.7 lbs; 37.9 kg
Kunmo LF-12100Deep Cycle
LiFePO4
75
100
100A cont.?25.3 lbs; 11.5 kg
Lossigy 12V100AhDeep Cycle
LiFePO4

100
50A cont.P: up to 10
S: up to 4
23.8 lbs; 10.8 kg
Lossigy 12V200AhDeep Cycle
LiFePO4
4D
200
100A cont.P: no limit (10?)
S: up to 4
46 lbs; 20.9 kg
Lossigy 12V300AhDeep Cycle
LiFePO4
4D (6D)
300
200A cont.P: up to 10
S: up to 4
72 lbs; 32.6 kg
Lossigy 12V400AhDeep Cycle
LiFePO4
4D (6D)
400
200A cont.P: up to 10
S: up to 4
95 lbs; 43 kg
Mighty Max ML100-12LIDeep Cycle
LiFePO4
30H
100
100A cont.
200A 15s
P: up to 4
S: not allowed
29.54 lbs; 13.4 kg
Mighty Max ML4D-LIDeep Cycle
LiFePO4
4D (6D)
200
P: up to 4
S: not allowed
48 lbs; 21.8 kg
PacPow 12V 100AhDeep Cycle
LiFePO4
31
100
100A cont.
300A 10s
P: up to 4
S: up to 4
27.56 lbs; 12.5 kg
Pionergy 12V200AhDeep Cycle
LiFePO4
4D (6D)
200
200A cont.P: up to 4
S: up to 4
46.1 lbs; 20.9 kg
Pionergy 12V300AhDeep Cycle
LiFePO4 
4D (6D)
300
200A cont.P: up to 2
S: up to 4
71.2 lbs; 32.3 kg
Power Queen 12V100AhDeep Cycle
LiFePO4
31
100
100A cont.P: up to 4
S: up to 4
25.25 lbs; 11.0 kg
Power Queen 12V200AhDeep Cycle
LiFePO4
4D (6D)
200
100A cont.P: up to 4
S: up to 4
48.28 lbs; 21.9 kg
Power Queen 12V300AhDeep Cycle
LiFePO4
4D (6D)
300
200A cont.P: up to 4
S: up to 4
62.8 lbs; 28.5 kg
Renogy RNG-BATT-LFP-12-50Deep Cycle
LiFePO4

50
50A cont.P: yes
S: not allowed
14.77 lbs; 6.7 kg
Renogy RBT100LFP12S-G1Deep Cycle
LiFePO4

100
100A cont.P: yes
S: not allowed
26 lbs; 11.8 kg
Renogy RNG-BATT-LFP-12-170Deep Cycle
LiFePO4

170
125A cont.?46.3 lbs; 20.97 kg
Scream Power 12V100AhDeep Cycle
LiFePO4
31
100
?P: ?
S: no
24.3 lbs; 11 kg
Scream Power 12V400AhDeep Cycle
LiFePO4

400
400A cont.
800A peak
?81.4 lbs; 36.9 kg
Vatrer 12C 100AhDeep Cycle
LiFePO4
31
100
100A cont.P: up to 4
S: up to 4
33 lbs; 15 kg
Vatrer 12V 200AhDeep Cycle
LiFePO4
4D
200
100A cont.P: up to 4
S: up to 4
48.5 lbs; 22 kg
VMAXTANKS LF27-12100Deep Cycle
LiFePO4
27
100
125A cont.
350A 3s
P: up to 4
S: up to 4
25.3 lbs; 11.5 kg
VMAXTANKS LFPU1-1245Deep Cycle
LiFePO4
U1
45
45A cont.
100A 3s
P: up to 4
S: up to 4
10.8 lbs; 4.9 kg
VMAXTANKS VPG12C-50LiDeep Cycle
LiFePO4
U1
50
50A cont.
100A 5s
150A 3s
P: up to 2
S: not allowed
12 lbs; 5.5 kg
Waterblade LFP 100-12.8Deep Cycle
LiFePO4

100
80A cont.
400A 1s
?29 lbs; 13.2 kg
Weize FPLI-12100AHDeep Cycle
LiFePO4
31
100
50A cont.
100A 3s
P: up to 4
S: up to 4
26.4 lbs; 12.0 kg
Weize TPLI-12200AHDeep Cycle
LiFePO4
4D (6D)
200
100A cont.
200A 3s
P: up to 4
S: up to 4
27.6(?) lbs; 12.5(?) kg
Wingda W100-12V100AHDeep Cycle
LiFePO4
31
100
50A cont.P: up to 4
S: up to 4
23.8 lbs; 10.8 kg
Wingda W200-12V200AHDeep Cycle
LiFePO4
4D (6D)
200
100A cont.P: up to 4
S: up to 4
48.9 lbs; 22.15 kg
Wingda W300-12V300AHDeep Cycle
LiFePO4
8D
300
200A cont.P: up to 4
S: up to 4
70.54 lbs; 31.95 kg
Zooms 12V 100AhDeep Cycle
LiFePO4
31
100
100A cont.P: up to 4
S: up to 4
25.35 lbs; 11.5 kg
Zooms 12V 200AhDeep Cycle
LiFePO4
4D (6D)
200
200A cont.P: up to 4
S: up to 4
49.6 lbs; 22.5 kg
Zooms 12V 300AhDeep Cycle
LiFePO4
4D (6D)
300
200A cont.P: up to 4
S: up to 4
62.83 lbs; 28.5 kg

It is a good idea to over-dimension the battery pack when figuring out how many batteries are needed to power a 3000 Watt power converter since, in most cases, energy needs can only increase.

And whatever You do, remain careful.

Although these devices are simple to operate and keep up, they are not toys and may deliver strong currents that can cause severe harm, accidents, or worse.

How Many Batteries For 3000 Watt Inverter Videos Suggestions From Youtube

3000w inverter, 400w Solar and 4 batteries. How I use it in my RV – Stim Racing Trailer and Travels
Cheap 3000W Reliable Inverter, DIY Powerwall, Chevy Volt Batteries – DavidPoz
3000 watt inverter power consumption – EFFICIENTSELF

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Written by Bob Matsuoka
Bob Matsuoka is a blogger and founder of RVing Beginner blog. He has been blogging for over five years, writing about his own family’s RV adventures, tips for people who are interested in buying an RV or taking their family on an adventure by RV.