I thought I would look at Inergy's potent little power storage and generator unit, the Apex, and see what the excitement is all about. First, lets look at its specifications:
As you can see, the Apex has some very nice, modern port and power handling features and is even expandable. Lets take a closer look at each power spec and see what we can learn.
Internal battery : Lithium NMC – the NMC part stands for Nickel-Manganese-Cobalt, which is beginning to overtake iron-phosphate as cathode material. Li-Phosphate batteries, have superior current rating and cycle life and are also more rugged when subjected to high voltage recharging over long periods of time. However, Li-NMC (nickel-manganese-cobalt) as cathode material is less expensive than iron-phosphate, and does have a lower power density. But regardless, lithium NMH is an extremely successful design with wide application from laptops to electric cars.
The Apex unit's 90 amp hour internal lithium NMC battery can be recharged from essentially empty, to full charge in 3 hours time. This is possible due to its 500 watt maximum power input rating, and assumes maximum solar production, but it does look to be a fair estimate. Here is why:
500 watts divided by 12 volts = 41.666 amp hours from the panels. I like to take half of rated power as a starting point to account for panel inefficiencies, clouds, etc, so that means about 20 amp hours from the solar array or potentially just over 4 hours to recharge the internal battery. Keep in mind that this is after draining it down to zero, which is something most people would not do because we're used to flooded batteries where discharging past 50 percent is considered abusive and will likely damage the lead plates by causing a process called sulfation. Sulfation prevents a lead battery from recharging to capacity, and if sufficiently advanced, cannot be remedied and the battery must be replaced.
Also, overcharging flooded batteries causes excessive heat and expansion often resulting in the loss of fluid. This can result in exposed lead plates, which also starts sulfation.
This is one of the distinct advantages of investing in lithium batteries to begin with; you can severely flog them and they bounce back for more abuse. They contain no lead sulfate, so sulfation is a non-issue.
This is just one of several reasons why, in my opinion, that for emergency or backup power, you want lithium batteries and their vastly superior power characteristics when compared to AGM, GEL or lead acid deep cycle batteries. But, as usual, I digress…
Battery Life Expectancy: 2,000 cycles or 10 years – a cycle or ‘charge-cycle' refers to the number of times a battery is discharged or put under load, then recharged. This is a wildly subjective reference though, so be careful here when comparing batteries with this metric.
Lithium batteries are game-changers when it comes to charge cycling. We are still used to older battery technology and the best practices for a lead acid battery are not the same as it is for lithium. Lithium batteries tend to last longer by limiting the amount of heat they are subjected to. Keeping them at full charge all the time, or deeply discharging and then recharging them to 100% capacity continuously will expose them to more heat and faster wear-out than with less aggressive discharge and less than full recharging.
Thinking back to your laptop with its lithium polymer or Li battery, most everyone has a friend or family member who has complained about their laptop battery failing despite always being plugged in. The failure was not caused by power cycling but rather by heat. Interesting that with lithium, a fully charged battery is warmer than a partially charged one. Frequent, less demanding power draws and partial recharges will result in the longest possible life with lithium.
The Apex 2000 cycle claim is reasonable as long as good practices are followed. Staying above about 50% discharge where possible, and using the unit in a way that doesn't ‘cook' it, should allow it to yield that many cycles. I have always placed at least one fan near any generator I've ever used, and would definitely recommend deploying one to help cool the internal battery of the Apex.
This brief and partial recharge profile of lithium is just about opposite of maximizing the potential of a lead acid battery. These do best with prolonged, slow charging and completely filling up to maximum cell voltage. They seem to take forever to soak up that last few percentage of charge.
AC Inverter: 1,500/3,000 watt surge, pure sine wave – A little small for my tastes, but likely determined by Inergy to provide the optimum total output for the amount of on board power storage. Nice that they built the Apex around a pure sine wave inverter, which increases the efficiency of the tool or appliance, and keeps its heat down among other benefits.
Given that battery-wise, the Apex is readily expandable, I'm a little surprised that a higher capacity inverter isn't offered. Perhaps this is something planned for a future version of the product?
MPPT Charge Controller: This feature allows the Apex to maximize the electrical output of the panel or panels connected to it. This also conveys to me that the Apex is a modern and updated power generator with thoughtful attention to detail.
3 Position Power Switch: This is another neat feature, the Apex can pass DC power through to several of its charging ports, USB, USB-C and 12V, without turning on the inverter. All inverters use power so keeping AC appliance use down will significantly add to the performance of the Kodiak.
EC8 Input Plug: This is a (please forgive the expression) total idiot-proof, one-way plug, and its also the same on both ends. The average person could make connections with this plug with eyes closed, by feel. Plus it is totally safe.
There really is much to like about the Apex Solar Generator. One thing that is easy to overlook is how small it is. Inergy managed to stuff everything, including the battery inside a box smaller than the last box of boots I brought home!
Dimensions are 14″ wide, 7″ height, 8″ deep. Weight is 25lbs, which feels dense, but its really not bad at all considering its capability. They also include a shoulder strap – because of its extreme portability, and a wall charger.
The Inergy Apex Solar Generator is proving popular with the camping community as well as with groups such as preppers and really anyone looking for a durable but small and potent power source. The Apex along with 500-600 watts of solar panels (500 watts input rating) would be an excellent companion for a person or couple at a remote campsite, or for emergency power backup to charge phones and laptops, run small refrigeration units and fans.
I would feel comfortable connecting up to 600 watts of PV modules to the Apex using 80% as an output efficiency estimate, this would yield 480 watts of power input to the generator. That is quite a lot for such a small unit.
If your power needs are somewhat light and you value portability, I don't think you could do any better than the Apex Solar Generator.
If you want a complete portable power generator system, right out of the box, then take a look at the new Enerplex Power Center. This system comes complete with solar panels, lights, extension cable, pure sine wave inverter, lithium battery and more. The specs show a carry weight of under 50 pounds for the whole enchilada. Be sure to check it out.