Collecting data from multiple SQL Servers

I'm sure there's a simple answer for this. I just don't know, how to do it. I need a way to collect data from multiple sql servers. I'm using the following code to fetch the data. (Not the real code). 

The code gets the VERSION info for a set of SQL Servers. I need a way to collect this information in an array or some sort of collection. 

Subsequently, after the FOREACH block, once I have the data at one place, I'll work on it. Thank you. 

$servers = 'srv1','srv2','srv3','srv4','srv5'

foreach($i in $servers) {

$sql = "select @@version"

#I need a way to collect the below result set in a variable  cummulatively
#if i just use some variable $res, data gets overwritten in every iteration 

Invoke-Sqlcmd -ServerInstance $i  -query $sql   -ConnectionTimeout 60 -QueryTimeout 99999

}