# Batteries for Beginners: Sizing and Charging for a 1600W Load

• Pula
In summary, Don provides a basic understanding of the battery industry and how sizing a battery can be complicated. He explains how to calculate time it will take for a battery to be fully charged back when AC power is restored, and how Peukert's Law can be used to help.
Pula
Hi,

I have just got into the battery industry and i would like to understand a few things especially when it comes to sizing a battery.

For example:
if i have a load of 1600W
and the system voltage is -48V DC (for a telecom application). The main supply is AC which is converted into DC through a rectifier in order to supply the load.

But during loadshedding for instance, or somehow the AC power is lost, I still need to back up my system for a certain period until the power is back.
Lets say 5 hours is needed to supply the load from a battery during the loss of AC.

Question 1: How do i select a battery that will supply the load with the right current and voltage?
(Examples are welcome as i know there are various batteries with different nameplates)
the battery that is used is an example, may it indicate the voltage of the battery and the capacity as well as the volts per cell.
Question 2: How do i calculate the time it will take for my batteries to be fully charged back when the power is back?
Question 3: how does the "Ah" of the battery play part in this scenario?

I have attached a snapshot that explains my scenario.

Thanks

#### Attachments

• Snapshot.jpg
9.9 KB · Views: 365
You first need to define the "right" voltage and current. You also need to specify number of charge discharge cycles and expected battery life.Are you talking about lead acid batteries? If so, then then Peukert's Law may be helpful to you,

There are many charging schemes. This article can introduce you to the ideas.

Pula
Pula said:
I have just got into the battery industry and i would like to understand a few things ...
This link provides a very good place to gain the understanding you're going to need.
http://batteryuniversity.com/learn/

dlgoff said:
This link provides a very good place to gain the understanding you're going to need.
http://batteryuniversity.com/learn/
Thank you Don. I have checked the link

## 1. What is the difference between battery sizing and charging?

Battery sizing refers to determining the appropriate size and capacity of a battery to power a specific load, while charging is the process of replenishing the energy in a battery that has been discharged.

## 2. How do I determine the size of battery needed for a 1600W load?

To determine the battery size, you will need to know the power requirements of your load, which is 1600W in this case. Then, calculate the energy consumption in watt-hours (Wh) by multiplying the power (W) by the time (h) the load will be used. Finally, choose a battery with a capacity that exceeds the calculated energy consumption.

## 3. What factors should I consider when choosing a battery for a 1600W load?

Besides the capacity, you should also consider the voltage, discharge rate, and type of battery. The voltage of the battery should match the voltage requirements of your load. The discharge rate should be high enough to handle the power demand of your load. Additionally, consider the type of battery, such as lead-acid, lithium-ion, or nickel-cadmium, as they have different characteristics and may be more suitable for certain applications.

## 4. Can I use multiple batteries to power a 1600W load?

Yes, you can connect multiple batteries together in parallel or series to increase the total capacity and voltage. However, make sure to properly size and match the batteries to avoid imbalances and potential damage.

## 5. How do I properly charge the batteries for a 1600W load?

To properly charge the batteries, you will need a charger with a suitable voltage and current output. The charger should also have the necessary charging algorithm for the type of battery you are using. Additionally, make sure to follow the recommended charging time and avoid overcharging the batteries, as it can reduce their lifespan.

• Electrical Engineering
Replies
11
Views
658
• Electrical Engineering
Replies
8
Views
1K
• Electrical Engineering
Replies
8
Views
1K
• Electrical Engineering
Replies
7
Views
1K
• Electrical Engineering
Replies
17
Views
1K
• Electrical Engineering
Replies
5
Views
2K
• Electrical Engineering
Replies
13
Views
1K
• Electrical Engineering
Replies
11
Views
2K
• Electrical Engineering
Replies
8
Views
1K
• Electrical Engineering
Replies
14
Views
2K