How to choose lithium battery for solar system? Low voltage lithium battery or high voltage lithium battery

We often wonder how to choose lithium batteries for a solar energy system, whether to choose high-voltage lithium batteries or low-voltage lithium batteries. From an engineer's perspective, I can give you some suggestions

If the lithium battery of a solar energy system exceeds 40KWH, I personally recommend using a high-voltage inverter + a high-voltage inverter

The reasons are as follows

Currently, the mainstream low-voltage lithium batteries on the market are 51.2V 100AH ​​(5.12KWH), 51.2V 280AH (14.336KWH) and 51.2V 314AH (16.076KWH)

First, if the low-voltage battery is connected in parallel for more than 2 clusters, it is best to add a battery junction box, which will increase the difficulty of installation and is not friendly to personal installation

Second, if more than 3 or more 51.2V 314AH are connected in parallel, the parallel current exceeds 450A, and the high-power load will cause the battery to overheat and affect the battery life. At the same time, excessive current will also increase power loss

Third, if For a 50KWH lithium battery, use 512V 100AH ​​(50.12KWH). The maximum current is 100A, which has little loss and is very friendly to the battery life.

Of course, a high-voltage lithium battery needs to be equipped with a lithium battery high-voltage control box. If a 512V 100AH ​​is used, the cost will increase (the lithium battery high-voltage control box and 100AH ​​lithium battery are not as cost-effective as 280AH or 314AH)

Normal household use rarely exceeds 40KWH lithium batteries. Using two 51.2V 280AH or 314AH is enough

The above is just a personal suggestion. If you have a better idea, you can contact us at any time to discuss it together

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