Your Mobile Computer Cart Battery Selection Guide

November 30, 2017

Author: Definitive Technology Group

Whether you're looking to save time and money in a warehouse setting or maximize up-time for a mobile computer cart at a large healthcare facility, you need to choose the right battery system to power your mobile computer carts. Mobile computer carts are one of the easiest ways to streamline workflows and increase productivity, but without adequate battery power, each cart could experience between 30-50% downtime.

With many different types of batteries to choose from, your only option is to wade through the technical specifications for each model - and isn't that the job for an electrical engineer?

This article offers a practical guide for choosing mobile computer cart batteries. You'll learn how to assess your needs in terms of up-time and power, and how to protect your team with product selections that are proven safe in commercial and clinical environments.




Start With Battery System Basics


It's important to understand the basics of batteries so you can distinguish a quality product and what's being promised by each manufacturer. The three things you need to know about a battery are:

  1. Battery Capacity - How many Watt-Hours does the battery provide
  2. Maximum Output - How many watts can the system safely deliver
  3. Battery Cycle Life - How many cycles you expect from the battery before you notice a reduction in runtime
  4. Charge-Rate - How long does it take to recharge the battery


Understand Your Power Needs


Everything that's plugged into your mobile computer cart will be running on battery power - that includes your computer, printers or other peripheral devices, and any other accessories that you need. Review the owner's manual for each piece of equipment to determine its power requirements (watts) and add them together to get a total.

Hourly power usage for a computer ranges from between 10W in sleep mode up to 100W per hour, depending on the model. Once you've calculated total power requirements, you can divide that number into the total battery capacity. Example: 240Wh / 30W = 8-hours of runtime. There are many other factors to precisely calculate runtime but this will provide some guidance.

Tip: The only way to perfectly understand runtime is to complete a trial of the workstation, electronic devices and battery within the environment that it will be used. No matter how well you understand battery technology, the human factors always impact the performance of these devices.


Battery Weight and Ease of Operation


Whether you're powering a single LED flashlight or a room-sized super-computer, there's a battery that can do the job - the key is finding one that meets your needs for weight and size along with power. There's no sense in putting a 50lb battery pack onto a mobile computer cart - it won't be too mobile with an extra 50lbs on it!

The right battery has to meet your requirements for power output without significantly encumbering your mobile cart - that's why we suggest modular battery systems that can be plugged-in to charge or swapped rather than a single large/heavy battery pack. That single pack will have more capacity but you'll be paying for it with an added 40-50lbs of weight on your mobile carts along with downtime for charging. You don't need a massive battery when you can simply hotswap. 

Remember, your employees will be pushing these batteries around for most of the day. Choose a modular system to reduce weight and configure the workstations to be as ergonomic as possible. It's worth it to invest in mobile computer cart batteries that are both powerful and functional - and there's no need to choose one or the other.


Make Safe Battery Chemistry a Priority


If you've ever seen a battery commercial, you've probably been bombarded with industry jargon about the "latest in lithium ion technology". Lithium ion batteries come in many forms, and it's important to understand what battery chemistry each product has so you can recognize the risks associated with each one:

  • Lithium Nickel Manganese Cobalt Oxide (NMC) - These batteries come with high energy density (capacity) and are lightweight but they suffer from shorter cycle life and are not as stable in catastrophic failure when compared to LiFE.
  • Lithium-titanate (NTO) and other remerging chemistries - Emerging battery technology offers rapid charge and discharge and a long cycle life, but at a "heavy cost" and lower relative capacity. With an energy density of just 65 Watt-hours per kilogram, you'll be adding 20lbs or more to your mobile computer cart to support this battery system and paying much more assuming you could find a manufactured, tested and approved emerging chemistry for workstations. Tip: they don't exist.
  • Lithium-Iron-Phosphate (LiFe) - LiFe batteries are by far the best option for the warehouse and hospital settings. This battery chemistry is inherently safer than other metal-oxide batteries - less heat is produced, and the battery won't feed itself with oxygen in the event of a fire or other mishap. LiFe batteries provide long cycle life and are cost competitive. The only downside to LiFE is that they weight slightly more and are slightly bigger but the performance and value far outweigh the negatives.

The FDA keeps records of adverse events involving medical cart batteries, including explosions, fires, and adverse events, do some research and it becomes crystal clear that LiFE batteries are the best option.


Battery Cooling Systems


Whether you choose a LiFe battery or some other chemistry, it's important that you consider how the system is cooled because it indicates the quality of design. We frequently promote the benefits of a fan-less system because they operate silently and do not collect/spread airborne substances but it goes far beyond that. In a fan-less system, the components must be very rugged and high quality in order to manage the heat that is naturally produced within the system. When a battery system passes IEC60601-1 medical safety standards without the use of a cooling fan, it's more than a piece of paper, it's a badge of honor because the system is very well designed and will provide a very long operational life.




You don't have to be an electrical engineer or battery expert to choose the right battery system for your mobile computer carts. Start by figuring out how much capacity (watt-hours) you need to run your carts, then look for a safe and lightweight battery system that meets your runtime requirements in a cost-effective way.


Similar Article


Anton Bauer Exits the Medical Industry—But Definitive Can Support Your Existing Cart Fleet

Read More