It’s only been three months since the batteries have been commissioned, but we’ve put together a preliminary list of pros and cons that we have observed during this period. There are some things we cannot comment on, for example long life and increased life discharge cycles, but we’ll continue to update the list if anything of importance arises.
- Require less maintenance - no checking water levels or specific gravity
- No equalizing needed
- No venting needed
- Can be discharged to a lower level than Lead Acid batteries,
- Has a Battery Management System (BMS) that protects against over-heating, over-current, over and under voltage
- Can be customized to fit your energy needs as well as dimensional requirements
- Has a smaller footprint than Lead Acid batteries
- Upfront cost could be up to three times more than what you might pay for a comparable LA battery
- Must be kept at temperatures above 0 C (32 F). In comparison, we saw battery temperatures of -16 C (3 F) on our LA batteries this winter in our unheated shop and they are still in working condition. This would limit the amount of locations, in comparrison to the LA batteries, that this storage system could be installed in.
- Even with the Low Battery Cut Off (LBCO) set from the factory at 48.0 volts and our LBCO on the Magnum Inverter set at 48.8 volts, we have still witnessed more than two occasions of having to manually reset the battery bank to bring the system online again. Recently we have installed Magnum’s networked Automatic Genrator Start (AGS) and we are no longer experiencing the issue, since the battery bank no longer reaches the LBCO set point. This does limit the amount of Amp Hours that are available. So it is no longer a 360 Amp Hour battery set that is able to be discharged down to 20%, it is more like a 360 Ah battery set that you can only discharge down to possibly 30% - 40%. (We are still testing this).
- At 48.0 VDC the Iron Edison BMS will shut down the battery bank to protect it from damaging the battery cells. This is a good stratigie for safegurding the battery but makes Solar and Wind production unavailable because there is no battery voltage to power the charge contollers and recharge the batteries. This becomes problematic in remote sites. With LA batteries there is usually voltage present (even at less than 10% SOC) and the ability to charge when the charging resource becomes available (Sun or Wind).
We still have much to learn, test and discuss about Lithium Iron Phosphate batteries in Renewable Energy applications.
Have any experience with using Lithium Iron in the Solar Electric world you’d like to share? Please comment below. We’d love to hear your feedback!