Using public chargers
Firstly, you do need either an Android or Apple smart phone to use most public chargers. This is because most chargers use an app to identify who you are and to sort out the payment. Some chargers use RFID cards to activate them, so you will need to get one of these from the provider before you can use the charger. No chargers currently use credit card chip and pin for payment, like petrol pumps, but this is coming in the future. If you don't own a smart phone, using public charging is going to be extremely difficult and you'll be limited to only a few chargers that use RFID cards. Even chargers that are free to use, they will normally require activating with an app on a phone to get your free charge.
It is advisable to install the apps and setup the accounts for each charger network at home while you have a good internet connection and plenty of time. Trying to do this at the charger, when you're in a hurry or maybe struggling with signal isn't a good idea.
Even when chargers offer a free charge to customers, you still need to use the app on a phone to activate the charger. The exception is Ecotricity rapid chargers that can often be on free vend and you can simply just plug in and select the connector on the screen.
Must have apps
Zap Map is the go to app or website for locating all the UK's chargers. It is also a great source for route planning, news and all sorts of EV related information. Using the website version of the map on your PC is great for route planning before you set off. Having the app on your mobile phone is a must for locating your nearest charger. Zap Map is always more up to date than in car sat navs.
The Electric Highway from Ecotricity
The Ecotricity chargers are the most common chargers on the major road network, with the 300 chargers primarily at most motorway service stations. Therefore, this will probably be your primary source for charging on the long trips. Charging is pay as you go (currently 30p per kWh), but you do need the app installed an an account setup to use the chargers.
Here is a video which shows you how to use the Ecotricity app and chargers.
If you buy your home energy (electricity and gas) from Ecotricity, charging on their public chargers is half price. More information.
Other apps you may need
This isn't a list of all the public charging networks, but just the common ones you'll likely need outside of central London and Scotland. You should check the areas you are travelling in on ZapMap and indemnify the chargers you'll want to use to check who operates them.
Pod Point have around 1,700 chargers that are typically at supermarkets, shopping centres or car parks. They are often free too, but you still need the app to activate the charger. When you plug in the car, the charger starts working for 15 minutes. During this time, you must activate the charger via the app otherwise it will switch off after 15 minutes.
The Polar network consists of around 6,000 chargers. Polar offer two way to use their network:
If you are going to use Polar chargers frequently, then you'll probably benefit from joining Polar Plus. For those that want to pay as you go, you use Polar Instant. You have to initially credit your account with £20, but then you only pay as you charge, from the credit in your account.
Some chargers on the Polar network are only available to Polar Plus subscribers, so check the payment information on ZapMap for each location.
Charge Your Car
Charge Your Car (CYC) is a payment system for various chargers around the country. They operate a pay as you go system, so you'll find it useful to have the app installed on your phone, with an account setup. You can see the location of CYC chargers on their website, app or on ZapMap.
Newmotion charge points are more prevalent on the continent, with 80,000 chargers across Europe. However, the UK network is growing and having a Newmotion account is getting increasingly handy. For users that don't have home charging, you may find there's on-street 7kW chargers near you here.
You can apply for a free RFID card or keyring fobs on their website here. Then you can either setup and manage your account via their phone app or via the website. There's no subscription fee as this is pay as you go charging,
PlugShare is an alternative app to ZapMap and used for locating public chargers. The difference is that it has worldwide coverage, so great if you're driving across the continent. Many UK residents offer their home charger for public use and traditionally put them on PlugShare, although ZapMap now offer this facility too now.
Ecotricity medium (22kWh) free chargers
There are still sixteen of the free Ecotricity 22kW charging posts (called "medium chargers") around the country. The location of these are detailed here. To use these chargers, you need a Ecotricity RFID card, as these charging posts do not use the phone app. The card is free, so it might be handy to get one if you're likely to travel in the location of these chargers. Note that the free charger at Oxford M40 services is broken and is unlikely to be fixed as they are installing new rapid chargers at this location which include a 22kWh AC port (not free and activated by the app).
Information for Oxfordshire drivers
Oxford Westgate charging
There are 50 free chargers in the Oxford Westgate underground carpark. These are located in the first level directly in front of you as you drive in, to the left of the central stairs. Currently they use blue traffic cones to reserve spaces for EV drivers, so you have to move the cone to park.
These chargers are operated by GeniePoint. While you can activate the chargers via their website (you need an account first), I've found it's near impossible to do in the underground carpark, even when using the Westgate guest WiFi. If you're going to park in the Westgate regularly, it is far better to purchase a GeniePoint RFID card, which costs £9, then you simply tap this card on the charger to activate your free charge.
Oxford M40 services
At the Oxford M40 services near Wheatley, there has never been AC rapid charging, but instead, a free to use 22kW AC charging post that need the Ecotricity RFID card to activate a charge. However, recently this charging post is faulty and looks like it isn't getting fixed.
In late December 2018, Ecotricity replaced one of the rapid chargers with their new model, which gives 50kW Chademo & CCS and a 22kW AC type-2 socket. This was the first installation of the new model charger on the Electricity network. So while there still ins't rapid charging for Renault Zoe owners at this site, at least there is 22kW AC charging. And you no longer need an RFID card.
If you drive a car that uses Chademo, CCS or Tesla, then there is a rapid charger for you at the Oxford M40 services.
Ecotricity old style 22kW AC charging post at Oxford Services
A very good video which explains how to access the main national charge networks