Batteries & Chargers

Q: "What is a Leisure Battery?"
Q: "What is a Deep Cycle Battery?"

• Leisure batteries are Deep Cycle Batteries, which are a kind of Lead Acid battery.
• They are designed for use in applications where they get left for a long time without being charged, and might only need to give out small amounts of power at a time.
• They are good for powering low energy things like window cleaning systems.
• They tend to live for more months than a vehicle starter battery when used to power a window cleaning system.
• They're good for heavy duty window cleaning uses such as window cleaning systems that are used hard all day or need to push water through extremely long hoses, or where the work is high above the vehicle etc.

Q: "What is a Gel Battery?"

• Gel Batteries are a kind of lead acid battery but they have stuff added to the acid to make it gooey (gel), meaning it won't spill if the battery is turned on its side.
• They are not able to provide very high power so if you need to do something particularly difficult then a liquid acid battery is more suitable. Of course this depends on the safety factors mentioned in the Lead Acid battery information (you couldn't use it in a trolley).
• Gel batteries charge quickly but have a shorter life expectancy than Lead Acid batteries.

Q: "What is a Sealed Lead Acid Battery?"

• Not as obvious as it sounds, It's a Gel battery.
• Sometimes called 'Maintenance Free Batteries'.

Q: "Why does my battery not work in the winter?"
Q: "Why does my pump keep stopping in the winter?"
Q: "My battery won't charge in winter!"

• Batteries, like many things, don't really like the cold. When you charge them in the cold they do not accept the same amount of charge as in summer. And neither are they very efficient when giving out the energy. So charging will be more limited and then using them is further limited, meaning power related problems often arise in very cold weather.
• Battery capacity (how many amps it can hold, not how many volts it can hold) is reduced as temperature goes down.
• Current draw by window cleaning systems (usage of amps) is likely to be slightly higher in cold weather.
• Batteries can lose some of their charge by just sitting unused. If leaving a battery idle for a long period of time, connecting it to an intelligent charger will extend the overall life of the battery.
• Increasing your frequency of charging to ensure the battery is always at maximum capacity is a good idea in winter.

Q: "Is my battery dead?"
Q: "Do I need a new battery?"

• Of course it is possible that your battery is dead but it could also be the charger that is at fault. A battery will only take as much charge as the charger will give it, so a fault with either with give the symptoms of poor battery charge. It's a good idea to test the charger as well as the actual battery.
• Split charge relays can also give a poor charge.

Q: "I put my gel battery on to charge and the charger has a green light but nothing works on the window cleaning system. What's wrong?"

• This sounds a lot like the battery has gone below the minimum level for the intelligent charger. What does that mean? Intelligent chargers are able to measure the battery voltage and of course are not expecting a 12V battery to have a really low voltage like 5V even when it needs a charge. So if you plug in a really flat battery they won't even recognise it. They just sit there with the green light on showing that there isn't even a battery plugged in! This is confusing because a green light is also what you would expect to see when the battery is fully charged!
• The overly discharged battery might be damaged by having been so flat but it also might not. We have successfully resurrected many batteries by simply putting them on a BC10 charger. These are not intelligent chargers so if you plug in a battery they will simply try to charge it, regardless of how flat it is. This will trickle a little charge into the battery, which in turn will raise the charge in there a little, and eventually there's enough in the battery for you to plug it to the usual trolley charger and carry on.
  • NOTE: Charging a gel battery on a non-intelligent charger requires care and attention and you do it at your own risk!
• Perhaps the bigger question is: "Why did the battery get so flat in the first place?" Most pump controllers are able to measure the battery voltage and warn the user that they need to charge the battery. If users ignore that message and continue working, the controller will eventually just shut down to prevent damage and overdischarging of the battery. So how did the battery get so flat? Maybe the low battery shutoff function had accidentally been switched off in the controller's menus.

Q: "I heard it's a good idea to run my battery right down before recharging it. Is that true?"

• Ideally yes. Batteries really need to be run down through their whole range of charge (10.5V - 13.0V) every time and if they then get a good slow charge they will take more charge and last longer overall. But in reality most window cleaners will use most of the charge every day and then not have enough to work tomorrow if they don't charge again. They therefore have little choice but to charge every night for tomorrow's day of work. Although some people like to use split charge relays these oftne don't give as much charge as you think they are, and you end up with battery issues anyway.

Q: "Do I need to top up my battery with deionised water?"

• No, leisure batteries are sealed so they cannot (and should not) be refilled. They will get a bit hot and give off a bit of gas when they are charging but they should not be opened and refilled. Overfilling them is actually bad for them and dangerous.

Q: "How do I know what the battery voltage is?"

• All Spotless Digital or Analogue controllers have a battery voltage indicator. Just select it on the screen or look at the LEDs and it will tell you.
• If your pump controller doesn't have this functions you will have to use a standalone voltage meter, as available from electrical stores.

Q: "I charged my battery but my controller keeps cutting out"
Q: "My battery is charged but the controller gives me a Low Voltage Warning"

• The power in the battery is not necessarily the same amount as what the pump controller will get. The power has to come through wires and connections and these all lower the voltage the controller actually gets. It might start off at 13.0V in the battery but be actually 11.0V by the time the controller gets hold of it.
• When the pump is running hard it will use more power than when it is not under load. This means the Amps in the wires will go up, draining the battery quickly, and also the Volts will drop in the wires. So the battery might have a good charge but the Voltage is getting lower as the pump is in use. To get an accurate idea of the 'real' voltage available, measure the battery voltage while the pump is running hard.

Q: "How low can my battery voltage get?"

• It is possible for it to get way down but it will be permanently damaged if it does. The minimum really is 10.5V. Anything under this will cause damage to the battery. For this reason pump controllers will switch off at that voltage. Pump controllers can detect the battery voltage and have been set to switch off at 10.5V or less to prevent this damage. The Spotless controllers can be manually 'unset' so they will not switch off. Users do this at their own risk and we would never recommend they do it. Some like to and the manual shows how to do it.

Q: "My battery has 12V in it but always runs out too quickly"

• There is a difference between Volts and Amp Hours. Amp Hours (Ah) is (in simple terms) how long a battery will last for when in use. Volts has nothing to do with that at all. So even if it shows 12.0V or even 14.0V it will not last long enough if the Amp rating (Ah) is too low. To get more work from a single charge of the battery you need a battery with a higher Ah rating. So a 110Ah leisure battery will last longer than an 85Ah leisure battery and both will last longer than a 22Ah gel battery. But they will all give the same 12V.

Q: "I got a bigger battery and it takes forever to charge"
Q: "How come my battery takes so long to charge?"

• The higher the Ah rating of the battery the longer it needs to be charged for (if using the same charger). Either use a charger which also has a higher Amp rating or just leave it for longer. For the battery the best is to charge for longer at a lower Ah rate.

Q: "Do I need a split charge relay?"

• These are designed to be wired into the engine (alternator) of the van and then gradually charge the waterfed pole battery over a long time. They do this as the engine is running. If you do a lot of driving then a split charge relay might give enough energy back into the window cleaning system battery. But for those living in more built-up areas these chargers are less likely to give enough to keep your system battery charged and running well. So don't be surprised if you still need to use a mains powered charger from time to time.

Q: "Does the SFC7 controller have a split-charge relay built in?"

• Yes, it will switch on the charging function for the leisure battery in the system and switch off when the engine of the van is stopped. So in effect, it is the same thing.

Q: "Do I need to have my engine running to use an SFC7 controller ?"

• No, you don't need the engine to be running unless the leisure battery is really flat. If that is the case then starting the engine will mean your Waterfed Pole system is running from the engine alternator and not the leisure battery.