Running multiple accessories from a battery

[Elnicko]

Morning all
As the title says, how many 'toys' is a safe option for running off a bikes battery. At the moment theres only heated grips and a quickshifter to lob on but if you start adding thinga like satnavs and the such is there really a limit before the battery becomes bogged down and can no longer do its job?

[Elnicko]

Think i should be alright. I've got a quickshifter with heated grips and satnav as an option to use but seems to work fine