After I have already tested, built or recommended various 12V and 24V LiFePO4 batteries or batteries, I take a closer look at a 48V LiFePO4 battery in this article and video. I tested the LiTime 48V 100Ah LiFePO4 battery, which comes in a modern rack metal housing. Due home improvement to its compact design, this storage system should be suitable for both smaller and larger solar systems. 48V storage can be connected to many common inverters. I took a look at the internal structure, did short-circuit tests and, of course, recorded capacity and charging and discharging curves. Company LiTime was formerly Ampere Time
The company LiTime is not really new, the Chinese company has previously marketed under the name Ampere Time already lithium iron phosphate storage (ie LiFePO4 batteries) via his shop as well as Amazon*. You probably remember our test of the 12V/200A Ampere Time Plus battery. The Ampere Time battery performed very well in our test, but also in many other tests. Ampere Time has meanwhile earned a pretty good reputation in the battery market, but the ratings and statements in communities are predominantly very positive. Thus, we should be able to expect that the change of name to the company name LiTime continues to stand for good quality. For this reason, I decided to test the LiTime 48V 100Ah LiFePO4 battery. Interesting for me is the 48V memory also because my solar system is slowly growing a bit and I will soon reach a limit where 24V still makes sense. The cables are twice as thick at 24V as at 48V, so I’m thinking about switching to 48V in the future. With the 48 V LiTime battery, I can also make some tests and performance comparisons throughout the year, especially of charge controllers. But more about that in another future article or video.LiTime 48V 100Ah LiFePO4 battery compact in rack
The nice thing about the LiTime 48V LiFePO4 battery is that it comes in a very compact metal housing. This is also called a rack battery because the battery can be inserted very well into a frame housing (rack) made of wood or metal. Two mountable brackets are supplied with which you can screw the battery to the frame. You can even stack several LiTime 48V LiFePO4 batteries on top of each other and take up relatively little space. One of the best-known suppliers who offers rack batteries reasonably affordable has so far been, for example, Pylontech. With the LiTime 48V LiFePO4 battery, Pylontech now gets real competition at low prices. The LiTime 48V LiFePO4 battery has a width of 46 cm at a height of just 18 cm. The depth is 44cm. Since up to four such LiTime batteries may be stacked on top of each other, very compact storage systems of up to 20 kWh (20000Wh) can be built with it, which is sufficient even for very large solar systems. Since many common inverters support custom 48V LiFePO4 batteries as standard, the LiTime 48V LiFePO4 battery can also be connected to many existing solar systems. Even widely used inverters that are often very common in guerrilla PV circles because of the simple connection type, zero feed-in support and the low price (e.g. Sun1000*) support 48V batteries like this LiTime rack battery. But also stand-alone systems or hybrid inverters such as the Victron MultiPlus II* preferably support such 48V batteries. Rack batteries are also a good alternative to 48V batteries, which you would have to build yourself from prismatic cells. Although a self-made is still the best solution because you can choose all components yourself, e.g. also a programmable Bluetooth BMS like the Daly BMS * can integrate, but you need some expertise when building yourself. Batteries of this size have to be built very carefully, in addition to specialist knowledge, craftsmanship and many tools are necessary (see 5000 Wh self-made project). If you don’t have that, then a rack battery in a metal housing is a nice alternative that is not so much more expensive. The 48V LiTime battery is not a lightweight
When the LiTime 48V LiFePO4 battery was delivered to us, I was amazed when a forwarding company delivered it on pallet. Until now, all other batteries had always been delivered by a parcel service. But somehow I could have imagined that, 4800 Wh is already a considerable capacity, which of course has its weight. Considering that many tested 12V batteries have already weighed about 20 kg, the total weight of the LiTime 48V LiFePO4 battery is almost a lightweight with just 43.6 kg. Nevertheless, when the large, well-padded package was parked in the hallway, I first had to think briefly about how to get this battery into my small workshop in the basement. It is definitely not a package that you move down narrow steep stairs. If you unpack it beforehand, this would be feasible in principle, because the case has two sturdy metal handles at the front, but it would be very tedious in any case. I then decided on the easier way with a stacking cart.
So the battery could then still be pushed quite comfortably, for the tests and measurements, in the workshop, so I could let you participate as usual in my video at the first unpacking (see video).At first glance, the LiTime battery looks very neat and cleanly processed. The built-in handles are really very helpful, later I often used them to transport the battery between different basement rooms (workshop / own solar system). It is not a hand pastry, but if necessary you can move it back and forth a few meters on your own. Connections and controls of the 48V LiFePO4 LiTime battery
As usual with a rack battery, all controls and connectors are located on the front of the battery. Basically, these are only the connection poles plus and minus as well as a 125A circuit breaker which also serves as an off switch. The connection poles are designed via a plastic base with two stable M8 screw connections each. The fact that there are two M8 connections per pole is quite practical, especially if you want to stack several such batteries and connect them in parallel. Series connections are not allowed, but also make little sense at 48V battery voltage because higher voltages would be quite unusual and dangerous.
Monitor capacity and currents via shunt
Further connections are not available, a digital interface as they also sometimes offer rack batteries, is not available with the LiTime battery. Somewhere, the manufacturer had to save something. In most cases, however, a digital interface is not really necessary, as charge controllers or inverters can very well determine when a battery is full or empty based on the voltage curve. Only the exact capacity that is still in the battery at a certain point in time cannot be determined so accurately without a digital interface. However, this can be easily retrofitted by, for example, switching a Victron SmartShunt* between negative line and consumer. As a result, a very accurate capacity display and digital interface (VE-Bus) has been retrofitted and can even monitor capacity and currents via app. In practice, such a Victron SmartShunt* or battery monitor* is often even more accurate than built-in interfaces, I had already described this shunt in more detail in this video or this article. An external SmartShunt also has the advantage that you can monitor the total current and total capacity of several parallel batteries. BMS of the 48V LiFePO4 LiTime battery