[Update: Jackery announced on 1/28/2021 that the updated Explorer 300 can now be charged through the 60W USB-C PD and be used in parallel with the 90W AC wall charger. This provides for a combined input of 150W, nearly cutting the charging time in half!]Back in April, I purchased the Jackery Explorer 1000 and the Goal Zero Yeti 500x later as a result of 2019's fires. Coincidentally, this year's fires on the entire US west coast is actually WORSE with new records broken! I cannot stress how important it is to be prepared for emergencies, and with a baby and young boy in our household, I wanted to ensure we have a crucial refrigerator running to store milk, medication, and whatever else we needed.There has been an increase in people taking emergency preparation more seriously.I had since invested in several car freezers (favorite is the Foho 34qt BCD-32) as part of my emergency toolset. When Jackery announced the Explorer 300 (E300) with a special launch price and some improvements over the Explorer 1000 (E1000), I jumped on it for one simple reason: my little boy loves camping, and I wanted him to have a mini-Explorer of his own (actually, I wanted another backup battery, but don't tell him that.) Literally, the E300 is a mini version of the E1000, and it looks awfully cute to have my son and I stand next to one another holding our own Explorers!Right off the bat, the two models are very similar to one another, and so I will be re-using much of what I had already written for the Explorer 1000. The E300 is the direct successor to the company's Explorer 240 model.CELL MANUFACTURERSToday's devices use Lithium-ion (Li-ion) and Lithium Iron Phosphate (LiFePO4) cells so they can pack more power in a smaller package and weigh less. However, Li-ion (which the Jackery is made with) also is more volatile whose risk increases as more cells are packed together. The quality of the battery cells and the BMS (Battery Management System) are crucial for safety.- Battery storage capacity is measured in Wh, and power output is in W (Watts)- The higher the Watt-hour (Wh) capacity rating, the more dangerous the battery could become if not handled rightBattery cells made by LG and Sony are among the best in the hobbyist world as are Sanyo/Panasonic, Samsung, and BAK Battery. Jackery Explorer 1000's batteries are made by LG and BAK, but the E300's are by EVE Battery. I do not have much information about the new, publicly-traded manufacturer's safety record, however, but going by Jackery's track record, they likely would not have selected a poor company to provide fuel cells for their power stations.During my years of research, I found that use of lower-quality batteries could pose a serious risk to life and property and should become a crucial part in deciding what to buy.IN A NUTSHELLJackery Explorer 300 is a relatively light power station with a professional-looking exterior and flashy, orange color scheme, and is backed by a company that appears, from the stories I have read (and personally experienced), to take customer service seriously. The batteries are made by a manufacturer I do not know much about, but their weight is an indicator that they are likely good quality. The 300W of energy (and peak of 500W) provides enough power for a small amount of electronics and small appliances, such as a laptop, television, mini fridge, medical device (like CPAP), and car freezers, but will NOT work for most rice cookers, and definitely not for a vacuum, water boiler, or circular saw.Like the bigger E1000, the hard, plastic material used to help shed weight (and cost) could be prone to cracking from hard falls or bumps, potentially exposing the Lithium-Ion batteries to puncturing. The fixed carry handle unfortunately cannot be folded, making it not ideal for packing things on top.Functionally, this is an excellent, portable power station with a multitude of AC and DC outputs, is solar charging capable with MPPT built in, and has a battery management system (BMS) to help ensure safety. Equally important is its verified claim of a pure sine wave - not modified - AC Inverter to produce clean electricity for sensitive electronics. Like Goal Zero Yeti 500x, Jackery finally upgraded the E300 with a USB-C PD with a 60W output. The E1000 only produces 18W. This makes it very useful for charging supported laptops.Jackery is one of Amazon's top sellers in the portable power station category with good customer service and reasonable prices, and as this is no longer my first experience with their products, I have no hesitation to recommend its latest product.PROS- At 293 Wh capacity, it is an improvement over its Explorer 240 model and falls in-between Goal Zero's Yeti 200x and 500x capacities-- Capacity to power a 30" LCD monitor and Mini PC for 3-5 hours, a Toshiba 50" Fire TV for almost 2.5 hours- Pure Sine Wave AC Inverter capable of continuous 300W power (and 500W peak) - More details later- Very well-priced at $349 at launch- Can power AC and DC (USB/12V Car adapter) at the same time (as long as they draw less than 300W combined)-- Laptop, tablet, phones, lights, fans, CPAP medical device, projector, TV, mini refrigerator, speaker, camera, DSLR battery charger, and SOME rice cookers- USB-C PD port outputs 60W- Can be used while charging- Faster charging with MPPT controller (Maximum Power Point Tracking)- Informative LCD with LED backlight-- Total power coming in (via solar panel or AC adapter)-- Capacity left (as a percentage)-- Total power (AC and DC combined) being used--- Suaoki G500 displays the Wattage separately for DC and AC, which I prefer-- Unfortunately, estimated hours to full charge or empty is NOT shown- BMS provides built-in overload, overcharge (automatically stops charging when the device is full), and short-circuit protection-- Multiple fans to keep the station's temperature safe- VERY compact at 9.1" x 5.2" x 7.8", though the higher-capacity, slightly larger Goal Zero Yeti 500x is still my favorite for its size and capacity- Portable at just 7.1 lbs- Bottom is well-protected by bright-orange, non-slip feet- Carry pouch included to hold AC charger and cables- Cigarette socket cable included- Unexpectedly good customer service-- Technical support was excellent in answering all my questions- 2 year warranty- Clear, well-written manual, though details were scarce-- Goal Zero's manual, on the other hand, is VERY detailed and helpful- Company is based in CaliforniaCONSThe E300 shares almost all the same design problems I disliked about the E1000, but also adds some improvements.- Batteries are not made by a globally well-known, Tier 1 manufacturer-- My unit came with fuel cells by EVE Battery, a China-based, publicly-traded company- No Anderson input port for solar charging-- You charge with an (optional) Anderson-to-8mm converter cable instead- Fixed carry handle cannot be stowed away-- Makes it difficult to stow things on top at the back of a trunk-- Upward-curved top (underneath the carry handle) does not allow small items to be temporarily stored on top- Hard, plastic material makes the power station lighter, but could be prone to cracking from hard falls or bumps-- Given that Lithium-Ion batteries become more volatile as capacity increases, one should handle the product with care- Although the exterior looks very professional, once I saw the Goal Zero Yeti 500x, I fell in love with the Yeti's design- Power buttons can be accidentally turned on/off through a single press (ie. while packing away your camping gear)-- Can lead to accidentally turning on/off the output during transport-- May unexpectedly find battery fully drained when you need it-- Suaoki requires you to hold the DC or AC button for 2 seconds before it turns on/off that output, helping to minimize accidental presses-- No automatic power off once no power is drawn/station has become idle- AC power brick is flat and large- No built-in flashlight or SOS signaling that the E1000 includes- Display is not as informative as I'd like-- Only shows battery charge level, input and output wattage, but no estimate of time remaining to full charge or to empty- Multiple fans turn on during high peak and can be too noisy for some- Battery cannot be replaced. This can lead to unnecessary landfill waste- Cannot be daisy-chained to other Explorer 300/1000's to extend battery capacity-- Some Goal Zero stations can be hooked up to other ones so power can be provided for an even longer time without needing to switch- Not waterproof. Keep it away from water splashes, rain, and pool!-- Lithium and fire or water can cause serious damage or injury!- No master power off button to turn off ALL outputs at the same time-- You have to manually switch off each type: DC, AC- No carry bag for the power station itself is included-- BUILT Willis 11" Insulated Lunch Box (ASIN: B08D6VMGG1) fits the E300 perfectly well (with usable pockets) when the Jackery is put on its sideINPUT PORTS- 1x 8mm-- Accepts up to 90W-- Max 12-30V and 8A with no minimum wattage--- WARNING: Do NOT use a power source/solar panel that exceeds 30V or 8A!---- Be mindful that solar panels that are daisy chained in sequence/series may output more than 30V combined!-- Can be used for solar charging--- MPPT charge controller is built in--- I recommend using a panel that's between 30W – 100W at 18V (with the right Amps to equal 100W)---- If you attach a 120W solar panel (with 12V x 10A = 120W), it will charge at only 90W--- I did not test solar charging as California is currently blanketed by smoke from the massive fires all over the west coast--- Jackery SolarSaga 100W charged the Explorer 1000 at an excellent 69-88W of input. I expect it to be similar with the E300OUTPUT PORTS- 2x AC with 3 prongs (120V)-- Inverter can handle a continuous 300W, peaking at 500W. More on that later-- Pure Sine Wave Inverter--- Ensures clean power to protect against damage to sensitive electronics--- Generates less heat--- Note: Some manufacturers claim to be Pure-Sine when they are actually Modified or Square Waves- 1x Cigarette socket (12V, max 10A)- 1x USB-C PD (5-20V, max 3A, max PD 60W)-- PD (Power Delivery) allows a device to be charged with up to 60W through the USB-C interface- 2x USB-A (5V, max 2.4A, max 12W)-- One of them is a QuickCharge 3.0 for rapid charging of compatible devicesUSAGE- To turn ON or OFF the Car/USB (DC) or AC outputs, press the corresponding button-- Note: This single-press (without hold) can lead to accidentally turning on or off the power station- To reset an Error condition that's shown on the LCD (ie. AC port is Overloaded), turn OFF the respective AC or DC output, and back on- To reset the Explorer, hold the DISPLAY button for 10 seconds- Li-ion batteries have 500 charge cycles before capacity drops to about 80% from when they were new-- Product could, in theory, be charged up to 2,000 cycles — about 1/4 of total capacity is lost every 500 cycle- Unlike LiFePO4 batteries, Li-ion can operate only in temperatures between 32-104F (0-40C)-- Jackery's Battery Management System (BMS) prevents:--- Recharging in temps outside of 32 - 95F (0 - 35C)--- Outputting power in temps outside of 14 - 104F (-10 - 40C)- Battery, like all Li-ion, slowly drains over time even when station is powered off-- Could take 1-1.5 years to go from full to emptyCONTINUOUS VS PEAK OUTPUTThe Explorer's AC Inverter provides a continuous output of 300W with a peak/surge of 500W- AC Inverter: Component responsible for converting battery (DC) power into AC for use by electronics- Continuous Output: As long as a device (or combination of multiple ones) does not exceed 300W, it can be used-- Example: A TV that uses 100W can be used because it is less than 300W. You can add more devices as long as they do not exceed 300W combined-- Example: A miter saw I have uses 1,800W, and because it exceeds 300W, it cannot be used- Peak/Surge: Almost every device temporarily draws more power when it is turned on. The highest amount it pulls during that time is the Peak/Surge. This Explorer can accept up to 500W-- Example: A TV that uses 200W (continuous) may temporarily suck up 400W (peak) when powered on. Because 400W is less than 500W (peak), this battery will allow the TV to turn on at that level for a few seconds (any longer, and it might cut power as a safety precaution). After a few seconds, the TV then only uses 200W (less than the continuous 300W limit) until the battery is drained-- Example: An unusual device that uses 250W (continuous) and surges to 1,500W when powered on would instantly be shut off by the Jackery. Why? Even though the device uses just 250W while already on, it jumps to 1,500W when powered on, exceeding the 500W surge limit of the JackeryCALCULATIONSThe below calculations are rough estimates as conditions, quality, and product age can vary.CHARGING TIMES- Wall charger: 4-5 hours-- AC adapter was observed to provide 76W when charging level was at 37%-- AC adapter will gradually charge slower as battery reaches full capacity (for safety reasons)- 100W solar panel: depending on weather conditions, it should take about 5-6 hours. I could not fully test this because the smoke from the California fires is blocking the sun-- WARNING: do NOT connect panels sequentially or you may output too much voltage and fry the power station! Connect them in PARALLEL with a Y-Branch cable- Goal Zero Yeti 500x can combine its 8mm and USB-C PD ports for a total input of 180W. Neither the E300 nor E1000 can combine both inputsHOW MANY WATTS DOES A DEVICE US?- Calc: Watts used by device = Voltage x Amperage- If a vacuum is 120V and 9.5A, it uses 1,140WIf a device draws more than 300W for an extended period of time, the power station will shut off as a safety precaution. This can also shorten the battery's lifetimeHOW LONG CAN A DEVICE BE USED FOR?- Calc: Hours available for device = Battery capacity (Wh) x 0.85 / Watts used by device-- Generally, about 10-15% of power is lost during power conversion- If a device uses 60W, it could last up to 4.1 hours (293 Wh x 0.85 / 60W)- Amazon TV I have uses about 100W-- If battery is full at 293 Wh, TV could run about 2.6 hours (293 x 0.9 / 100)HOW LONG DOES IT TAKE TO CHARGE A DEVICE?- Calc: Hours to charge device = Device's battery capacity (Wh) / Input Wattage- If a laptop accepts 60W of input and its battery capacity is 200 Wh, it could take 3.3 hrs to charge (200 Wh / 60W)HOW LONG DOES IT TAKE TO CHARGE THE EXPLORER 300 WITH SOLAR?- Calc: Hours to charge battery = Battery capacity (Wh) / (Panel Wattage x [0.5 or 0.75])-- In a perfect lab environment, solar panels charge at the indicated wattage (ie. 150W)-- Expect to only receive 50-75% on a good, sunny day (ie. 75W - 113W), depending on environmental conditions, panel's age, and component quality-- Tip: Even if it is overcast, the panels will STILL collect solar energy. Keep charging!- If a solar panel is rated for 100W, it could take as fast as 3.9 hours [293 Wh / (100W x 0.75)] to chargeHOW DOES ITS CAPACITY COMPARE TO POWER BANKS?- Calc: Powerbank-equivalent capacity (mAh) = Battery capacity (Wh) / Voltage x 1000-- 1 Ah = 1000 mAh- Explorer's 293Wh at 3.6V is roughly a 81,389 mAh powerbank (293 Wh / 3.6V x 1000) or a 27,129 mAh at 10.8VTIPS- Always test your devices with the power station before you depend on it on the go- Lithium-ion batteries are volatile-- To minimize fire damage to your belongings or loved ones, store the power station in the garage and not inside the house. Best storage is a dry, cool place, however-- You cannot bring a battery of this capacity on a plane- With the right BMS, quality batteries, and other factors, the power station can be stored in the car while camping during a hot, California summer-- Keep the battery out of direct sunlight. I usually store it on the floor of the car and crack open the windows a tiny bit-- Do not USE in the car if temperatures fall below or exceed the battery's rated, operating temperature (32-104F or 0-40C)Keep your car cigarette lighter with the power station -- you could plug it into its 12V DC socket for starting a camp fire- If using a car charger, make SURE you only charge this station while the car is RUNNING. Otherwise, you'll deplete your car's battery and leave you stranded- If charging with a solar panel, be sure to keep the station out of direct sunlight as it could overheat-- A solar panel is NOT required to use the battery-- Explorer 300 uses the MPPT solar charge controller--- Smarter, more efficient/expensive than PWM--- Suitable for larger systems- Can be used and charged at the same time. Manufacturers’ recommendations for their own products:-- Yes, that’s fine: Goal Zero, Jackery, Rockpals, nrgGo-- No/Not advisable: Suaoki- NEVER charge the power station itself in below freezing temperatures, or you will damage the Li-ion battery AND potentially limit its overall capacity-- You CAN use it to power OTHER devices because the generated heat will warm its battery enough to be within operating temps-- At below freezing temps, keep it in an insulated cooler and connected to a power source (ie. solar panels). The heat generated by the battery will keep it running as best as it can- Turn off any output ports (AC/DC) that are not being used in order to conserve power- Do not use any power station in a tightly enclosed area as it can overheat- To prolong the battery lifetime while in storage, keep the battery fully charged every 3-6 months-- Or, according to customer support, keep it plugged in when not in use and discharge it to 50% every 3-4 months-- NOT using the battery for a very long time can actually hurt its lifetime-- There is no "memory effect" in this station's battery. It is better to NOT let it completely drainFINAL THOUGHTSThe Explorer 300 is another winner for Jackery in that it has made several improvements over its older, bigger brother, the Explorer 1000. I was disappointed to find out that its batteries are made by EVE Battery, a Chinese, publicly-traded company I have little knowledge of. The Explorer 1000, on the other hand, used either LG or China-based BAK Battery, both of which are excellent manufacturers. The company has shown time and time again that it takes customer service VERY seriously, and to me, that is a major plus. The 300W of energy (and peak of 500W) provides enough power for a small amount of electronics and small appliances, and is the perfect size for my little boy, the fellow explorer and camper.The hard, plastic material commonly used by power stations to help shed weight and cost (just like the E1000) could be prone to cracking from hard falls or bumps, and as such, this product should be handled with care - a puncture of the Lithium-Ion batteries could cause severe harm. The fixed carry handle unfortunately cannot be folded, making it more difficult to pack things on top.Jackery is one of Amazon's top sellers in the portable power station category with good customer service and reasonable prices, and if the new EVE Battery manufacturer proves to be as reliable as other Tier 1 makers, I will have no hesitation to recommend its latest product.