Which 48 volt lithium battery is the best

**Isetech** · 01-Jul-22, 09:50 AM

When selecting the battery for your system, how would the C rating affect the design?

From the little experience I have installing inverters, you never want your system to be pulling 100% @100 amps if you are using a 100 amp/hr battery, especially if you are using the system as a backup (UPS type). You would need a pile of batteries if that is the case, then 0.5 or 1 C wouldnt be a a priority.

An example: If you are using it for critical/essential loads, which generally the case in SA, the system should not not be fully loaded at any point, you want the system to support your essential loads at any point of the day or night with at least 6 hours of support, preferably longer, but they budget would determine the support period. The longest life cycle would be the better option, not the higher C rating.

Another example would be a small workshop. A battery which can handle the full discharge capacity for short bursts would be a good option, because you might be running small machine with motors which start up. You are looking for a system to keep the workshop flow.

It all seems to keep going back to one thing, design for the application. The solar and inverter audits fails seem to point at bad design. Understanding and designing the system around the customers application seems to be the missing link.

**Justloadit** · 01-Jul-22, 10:17 AM

Originally Posted by Isetech

Could the C rating be reduced to protect "seconds" (not off the production line) batteries?

The BMS in the batteries, only provide 2 functions as far as I know.
1 - If the battery voltage drops below a predefined value, it disconnects the battery from the load. Gets enabled when the charger is enabled
2 - In the case of a short circuit, then the BMS will disconnect the battery from the load. I am not sure here but i think it is again enabled when the charger is enabled.

**Justloadit** · 01-Jul-22, 10:21 AM

Originally Posted by Isetech

When selecting the battery for your system, how would the C rating affect the design?

From the little experience I have installing inverters, you never want your system to be pulling 100% @100 amps if you are using a 100 amp/hr battery, especially if you are using the system as a backup (UPS type). You would need a pile of batteries if that is the case, then 0.5 or 1 C wouldnt be a a priority.

An example: If you are using it for critical/essential loads, which generally the case in SA, the system should not not be fully loaded at any point, you want the system to support your essential loads at any point of the day or night with at least 6 hours of support, preferably longer, but they budget would determine the support period. The longest life cycle would be the better option, not the higher C rating.

Another example would be a small workshop. A battery which can handle the full discharge capacity for short bursts would be a good option, because you might be running small machine with motors which start up. You are looking for a system to keep the workshop flow.

It all seems to keep going back to one thing, design for the application. The solar and inverter audits fails seem to point at bad design. Understanding and designing the system around the customers application seems to be the missing link.

Agreed, full C in my opinion should be reserved for instantaneous requirement of any load for a short period of time.
I usually like to cater for at least 6 hours of load on my battery pack, preferably 10 hours.
At 10 ours it ensures longer battery life due to the reduced period of charge time at a high rate to bring the capacity up to cater for the constant load shedding experienced in recent days.

**Isetech** · 01-Jul-22, 11:54 AM

I see Sunsynk have 2 types of batteries

CATL Battery SSLB1

BYD Battery

**Gene** · 14-Jul-23, 12:50 PM

I got a 10 year guarantee for a DYE battery connected to a luxpower inverter, very happy with it.

**Isetech** · 14-Jul-23, 01:32 PM

From my experience installing batteries, my first choice is an IP 56 Susnsynk battery.

The reasons:

10 year warranty

All the battery data is visible on the inverter screen, including cycles.

They are IP 65 rated , ideal for the coast were I do most installations.

**jennyzhang** · 19-Sep-23, 05:44 AM

What is C rating?
A C rating is a rating of how quickly a battery can release energy. This rating is combined with the capacity of the battery to determine the maximum discharge.

This is very important when you are considering battery selection for your solar electric system. Especially if you have some high power heating type appliances, they tend to pull a lot of current from the battery side the moment they are turned on.

How do you calculate the C rating?
Let’s take the EVE 3.2V 280Ah LFP battery cell as an example.

In the specification, the charge/discharge current is 1C and the maximum charge/discharge current pulse is 2C (3s).

So,
Continuous charge/discharge current = 280Ah x 1C = 280A.

Maximum charge/discharge pulse current = 280Ah x 2C = 560A.

**HGTesla** · 22-Sep-23, 04:29 AM

Choosing the appropriate 48-volt lithium battery type depends on specific requirements and application scenarios. Ensuring compatibility with the inverter or solar power system and meeting specific needs is crucial.