Anonymous asked in Cars & TransportationMaintenance & Repairs · 3 weeks ago

Does anyone know a good external battery that can run a laptop for 4 hours (when the reg.battery is out)?

3 Answers

  • 3 weeks ago

    It's called an Uninterruptable Power Supply, of which there are many around of varying capabilities.  They're designed to run a computer when the mains power is out, so will do the same for your laptop.

  • Mmm J
    Lv 7
    3 weeks ago

    I do!

    Background: I live in California. We are now under threat of rolling blackouts due to high winds and wildfire potential. There have been three seasons here for many years (wet, dry, fire), so the fires are not new, but because the power companies have been sued (and lost) because their power lines went down, sparked and caused some of the wildfires. So... now when it is really dry, gets windy and the humidity is low, the power companies de-energize certain power supply lines. I've been working from home for nearly 10 years.


    My laptop, an iMac, three 21" external monitors, the internet cable/mode and a network gigabit switch all get their power from a "solar generator" when commercial power goes out.

    Option 1:

    There is a 100 amp-hour LiFePo battery connected to a 1000 watt AC power inverter and all the computers, monitors and network equipment are connected to it. The battery is also connected to a 60 amp MPPT solar charge controller and two 160 watt flexible solar panels. The battery, weight about 25 pounds. Everything fits in a rather large rolling tool case, so it is portable. I've taken it camping... When fully charged, this power solution can power everything for about 8 hours before it needs to be recharged. I made this... the battery, MPPT charge controller, toolcase, inline multimeter, cables, solar panels, 200 amp fuse, AC power inverter, power source automatic switch, red & black 14 gauge wire, 0/2 battery cables and battery terminals comes in at about $1,500 and about 60 pounds. This is more than you need... so...

    Option 2: Before I made the solar generator, I plugged the laptop, monitors, iMac, and network equipment into a CyberPower 1500 volt-amp computer back up system. It was able to provide power for about 4 hours. It has an automatic switchover built-in so when commercial power goes away, the batteries take over. Amazon has them for about $155. A UPS this size weighs about 25 pounds.

    This also more than you need... BUT. You did not tell us which laptop. I use a HP Elitebook 745. The internal battery provides ~ 6 hours battery time. I've been looking into "universal laptop battery"... MaxOak looks interesting with 50 amp-hour back-up. Since we don't know which laptop you are using, we don't know it's power consumption requirements so we don't know how much power is needed for your required "4 hours".

  • Anonymous
    3 weeks ago

    I don't know really

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