Thread: What can be run off a 12v 100 amp/hr battery?

Yes, you'll need an Inverter of greater watts than your appliances.

you can run anything you want keeping the following in mind.

A normal lead acid battery will only come up to about 85% capacity off an alternator unless you have something like a xantrax 3 stage regulator fitted. An agm sealed lead acid like full river will come up to about 95%. The most you should discharge your battery is by 50% so in reality you only have around 40 or so amp/hours available from a 100 amp/hout batt. you cann do more but everytime you flatten it say under 11.5 volts you halve the effective cycle life. do it again and you halve it again. The bigger appliance you run the quicker you will flatten it. So always keep them charging up and near full.

By converter i take it you mean inverter. If it is a cheaper one it will put out a coarse sine wave that will run most drills and appliances as long as the wattage is up to scratch. To run some flouro's, charge mobiles and computor equipment or most other technical things you will need a pure sine inverter. alot more bicky's but better in the long run. You can run anything off them. The main point is to be careful what you run off the cheaper ones, some things just wont run but you can damage your equipment that requires good quality electricity. Hope this helps

The Colonol

Originally Posted by popotla

Now, maybe I’m asking a stupid question, but using a !00 amp/hr 12 volt battery (fitted as an auxiliary in a LR Defender) and a converter/adaptor, if needed, is it possible to run stuff like a 220-volt blender or juicer (things that normally run off the mains)?

Hi popotla, as Vern posted, make sure your inverter is big enough to be able to provide the power needed to run your blender/juicer.


A good rule of thumb is to make sure your inverter is capable of supplying at least 50% more power at a continuos at that the maximum power of your device. EG, if your blender pulls 1000w the you should use an inverter with a CONTINUOS rating of 1500w.

There are a number of reasons for having the extra 50%, the main reason is that modified sine wave ( the cheaper ones ) start to change the output wave shape as the inverter approaches it’s maximum output so by keeping well below the inverter’s maximum, you should have no problems powering any 240 vac device.

Next, with any electrical device that has a motor, AC or DC, there can be a need for a huge start up current surge to get the motor running so you need to have a fair bit of extra power to play with or the inverter will simply trip it’s overload circuitry every time you try to start your device.

Cheers.

Originally Posted by Col.Coleman

you can run anything you want keeping the following in mind.

A normal lead acid battery will only come up to about 85% capacity off an alternator unless you have something like a xantrax 3 stage regulator fitted. An agm sealed lead acid like full river will come up to about 95%. The most you should discharge your battery is by 50% so in reality you only have around 40 or so amp/hours available from a 100 amp/hout batt. you cann do more but everytime you flatten it say under 11.5 volts you halve the effective cycle life. do it again and you halve it again. The bigger appliance you run the quicker you will flatten it. So always keep them charging up and near full.

By converter i take it you mean inverter. If it is a cheaper one it will put out a coarse sine wave that will run most drills and appliances as long as the wattage is up to scratch. To run some flouro's, charge mobiles and computor equipment or most other technical things you will need a pure sine inverter. alot more bicky's but better in the long run. You can run anything off them. The main point is to be careful what you run off the cheaper ones, some things just wont run but you can damage your equipment that requires good quality electricity. Hope this helps

The Colonol

Hi Col.Coleman, sorry mate but there’s lots of misleading info in your post.

There is no reason why you can not charge any automotive battery to at least 95%, some types take longer than others but all can be fully charged off an alternator.

As there is no effective way to determine if a battery is 100% charged, while the battery is in a vehicle so 95% charged is fully charged.

Next, you can discharge any battery down to 20% SoC ( about 11.58v ) and altho you will shorten is operating life, it is nothing as drastic as you posted.

You need to see a battery manufacturer’s specific graphs to see what the number of cycles are likely to be if you discharge their battery down to a given SoC.

For a VERY rough example, if a manufacture states that you can get 1,500 cycles from one of their batteries if you don’t discharge it below 50% SoC ( about 12v ), then you might only get 200 cycles if you discharge the battery to 20% SoC ( 11.58 ) and 50 cycles if you discharge it down to 10% SoC (11.3v ).

The 200 cycles may not sound too good but if you factor it into the context of how you are going to use the battery, then if you are going to use the battery every weekend and discharge down to 20% every time you use it, you are only going to get 4 years use out of the battery.

As most flooded wet cell batteries usually only have about a three to four year life expectancy, what’s the problem.

Now, if you only discharge to 30% SoC ( about 11.75v ) then you might expect to get about 300 cycles of use or 6 years.

Note, most AGMs can be taken lower but they will still have roughly the same effects.

In all cases, there are a number of other major factor that have to be considered when trying to determine just how low you can take a battery and still expect to get a good operating life span from that battery.

Cheers

the batteries I run are full river hgl agm's. over 26 ah they have a 10 year design life. I have personally run them down to 4.7 volts trying to run an old engel and they havn't died yet and that was over 3 years ago. On advice from some 12 volt specialists that is the formula I use to determine power needs taking into consideration cycle life v depth of dicharge, recharge times and safety margins. Yes you can get them to a mythical state of fully charged but as you know with a constant voltage and not a true 3 stage charger the nearer you get to full the longer it takes. I have gotten mine to 13.5 volts off a supercrap 2.5 amp single stage charger. I wasn't trying to mislead, just provide some safety margin in the calculations.
I love the agms as they are more suited to 4wd applications than the wet acid batt and deep cycle batts due to the way they accept charge, depth of discharge and they don't mind being abused. Roll them over, shake them, start and winch off them or run a fridge for three days and boost charge them super quick. they just don't care.
Sorry if I caused harm. Maybe we could get technical in another thread section.

Cheers
The Colonol

The Landrover dealer here (Salalah, Oman) today told me that “a blender and juicer can’t be run off a 12-volt battery”. I replied that I had a different opinion, and armed with the info given by the posters above, blinded them with science by asking whether a pure sine inverter wouldn’t do the trick. Then they changed their story.

Col. Coleman said “I love the agms as they are more suited to 4wd applications than the wet acid batt and deep cycle batts due to the way they accept charge, depth of discharge and they don't mind being abused. Roll them over, shake them, start and winch off them or run a fridge for three days and boost charge them super quick. they just don't care.”

Landrover thought an AGM was a make; no-one had heard of them.

As a second battery, Landrover propose fitting a Delphi YGD 100860, 100 amp/hr, sealed for life (as already fitted to Defender as main battery.) This would be in parallel (tandem?) with the main one, with a manual cut-out between them so that power cannot be taken by accessories from the main battery, if the second one has run down.

Does this sound OK? Is there any chance that this Delphi model IS an AGM? I can't seem to find out about it on the internet.

Originally Posted by popotla

Now, maybe I’m asking a stupid question, but using a !00 amp/hr 12 volt battery (fitted as an auxiliary in a LR Defender) and a converter/adaptor, if needed, is it possible to run stuff like a 220-volt blender or juicer (things that normally run off the mains)?

.......or you could do what I do when I go camping....I just take my brekky orange juice already squeezed in a 2 litre bottle....generally I buy it at Coles or Woolies

Mate agm stands for absorbed glass matt. As for as I know the electolite is held stable by glass fibre matting in a gel form(waiting for help here from drivesafe) and are a sealed batt. There are also sealed gel batteries. I am unfamiliar with delphi but I think I have heard the name somewhere but can't comment on them. Surely some info should be somewhere or beware. Parralel is the way to connect batteries as connected in series you double the effective voltage(+ to - as in 24 volt trucks). You do need to isolate your house batt from your starter batt and there are many different ways from simple manual switches and voltage sensitive solinoids to more elaborate sytems. Have found manual switches the best in combination with the automated systems as I tend to abuse mine and when the batteries parralel the voltage drop clicks the relay in and out. It's simpler to switch to batt 1 or 2 or parralel, it just takes some thought, but most of the time the auto switch takes care of the job. I have 2x120 ah batts plus another 3x120 ah in the trailer so run alot of big cable and have a trick regulator. High beam alone so far pulls 45 amps.

Where the hell are you anyway?