Does anyone use a car inverter to charge their battery on-the-go?

[Bike Gorilla]

Looking at doing this for topping up when driving to different destinations. Don't understand what I would need (voltages etc.) and electric is like voodoo to me!

 

[jimbob]

Have a look for 12V investors. I'd suggest a minimum of 500W.

You may want to be careful using the cigarette socket to power it from for long periods as it may not be able to supply the power without overheating. Do you know what power your charger uses? Much above 100W and you may be pushing it.

 

[R120]

Search results for query: invertor

www.emtbforums.com

 

[RickBullotta]

I use one of these (along with my 56V batteries from my lawnmower, chainsaw, trimmer, snow blower, and hedge trimmer) to power a E6002 Shimano charger so I can charge anywhere. Works great.

Power+ Nexus Escape (150W Power Inverter)

Built tough with a 120V AC power outlet & 2 USB ports. Use any EGO battery to power the Escape. Battery sold separately.

egopowerplus.com

 

[flash]

watts = amps x volts.

Look at the bottom of you charger. It'll tell you what amps it requires (input AC power not DC output) and then multiply that by the voltge where you live. Get an inverter that can output that many watts. Often, an inverter over 200 watts will not be suitable for a cigar lighter connection and it draws too much current and will need to be wired to the battery directly.

Here in Oz my Shimano charger needs 2.5 amps peak power. So multiply that by 240V and I need an 800 watt inverter. In my system I have that connected to a second (leisure) battery system as I don't like using my starter battery for charging applications on high draw devices.

Gordon

 

[carlbiker]

Interesting I’d be interested in knowing how to power batteries too, is solar an option or is there just a nice low maintenance boat battery or something capable? Like if a fast charge is 6A then I think that’s like 120 watts required from solar or something else resulting in 50% charge in an hour right?

I could be talking out of my ass though...

 

[carlbiker]

I use one of these (along with my 56V batteries from my lawnmower, chainsaw, trimmer, snow blower, and hedge trimmer) to power a E6002 Shimano charger so I can charge anywhere. Works great.

Power+ Nexus Escape (150W Power Inverter)

Built tough with a 120V AC power outlet & 2 USB ports. Use any EGO battery to power the Escape. Battery sold separately.

egopowerplus.com

Looks great £299 though..... might as well buy a second battery maybe

 

[RickBullotta]

Looks great £299 though..... might as well buy a second battery maybe

Yikes. Only $99 here in the US (since I already have the batteries from my tools).

 

[carlbiker]

Yikes. Only $99 here in the US (since I already have the batteries from my tools).

Have a link?

 

[flash]

Interesting I’d be interested in knowing how to power batteries too, is solar an option or is there just a nice low maintenance boat battery or something capable? Like if a fast charge is 6A then I think that’s like 120 watts required from solar or something else resulting in 50% charge in an hour right?

I could be talking out of my ass though...

*If* your bike has a 12V charger available, it'd be technically possible but practically a PITA to charge directly from Solar. Your 6 amps times 12V means a 720 watt output from the panels. That's a LOT of solar. Like a LOT. Most portable panels max out at 200 watts. Likely you'll need a lot more than 720 as well as solar loses efficiency quickly outside ideal conditions. In practical terms you need to charge from another battery. And for most brands you need to charge from AC so that means an inverter.

A 100aH leisure battery at 12.8V has 1280wH of power. 80% is available from a lithium system and 50% from an AGM (or you'll damage the battery) Say you have a 504wH battery on your bike. That's 2 charges from lithium and 1 charge from AGM (assuming a 100aH leisure battery). You'll need an inverter to run your charger that has about a 20% loss in efficiency. My Shimano charger requires just under 700 watts peak power. (240V, 2.5amps and 20% loss of efficiency) You'll also need to ensure your battery can output enough current to drive the inverter. So 700 watts per hour or 60 amps per hour.

Basically for a 100aH liFePO4 battery, charger for it, case and an 800 watt inverter you need to spend AUD 1200-1400 or 650-750 Pounds/Euro.

Gordon

 

[Bike Gorilla]

THanks everyone, it does sound harder than just plugging an inverter in to my cigarette lighter! The last thing I want to do is damage the battery too. I'll maybe leave it for now. I don't often feel like riding after I've gone through the battery anyway!

 

[flash]

THanks everyone, it does sound harder than just plugging an inverter in to my cigarette lighter! The last thing I want to do is damage the battery too. I'll maybe leave it for now. I don't often feel like riding after I've gone through the battery anyway!

A lower power inverter won't damage your bike battery. Either you'll get a slow charge or no charge. The inverter may trip into safe mode. But your bike battery will be fine as long as you're using the factory charger.

Gordon

 

[carlbiker]

So for us mere mortals who haven’t the foggiest how much would it cost to own the right battery abd be able to charge the bikes?

 

[routrax]

So for us mere mortals who haven’t the foggiest how much would it cost to own the right battery abd be able to charge the bikes?

@flash is spot on with his post.
I think if you want to charge off-grid then a small petrol generator might be the least hassle option. You can get something reasonable for under £500. This means you would only have to pick up a can of petrol and you're good to go, no worrying about charging and/or destroying batteries (It's almost guaranteed that you will destroy a battery if you don't know how to look after them).

I've been using Kipor gennies for about 10 yrs and they seem like they're at the higher qualiity end of the chinese gennies available. The Honda EU series is gold standard for small gennies, but will start at £800-900.

 

[Bike Gorilla]

Thanks. I was thinking more of charging while driving, so while the engine is running. So I think an inverter will do the trick.
the question now is, which one!? Appreciate any UK links to some contenders

 

[routrax]

Thanks. I was thinking more of charging while driving, so while the engine is running. So I think an inverter will do the trick.
the question now is, which one!? Appreciate any UK links to some contenders

Ah, right A gennie probably isn't the thing for that!
You could gamble on a 'car invertor' that plugs into your accessory socket, but you'd want to make sure the in situ wiring could cope with the demand, or it could get a little smokey or worse on the drive.

I'd put in a dedicated feed from the battery with a voltage sensing relay to switch the feed on when the engine is running. But I'm with @flash in not liking charging high draw things on the car system as it's really only designed for the car and couple of phones etc.

I've got an 800w Victron invertor and 2 100ah leisure batteries in my campervan. This works well, but it's expensive and takes up space.

Maybe get a spare battery and make sure both are charged before you leave!

 

[Bike Gorilla]

Ah, right A gennie probably isn't the thing for that!
You could gamble on a 'car invertor' that plugs into your accessory socket, but you'd want to make sure the in situ wiring could cope with the demand, or it could get a little smokey or worse on the drive.

I'd put in a dedicated feed from the battery with a voltage sensing relay to switch the feed on when the engine is running. But I'm with @flash in not liking charging high draw things on the car system as it's really only designed for the car and couple of phones etc.

I've got an 800w Victron invertor and 2 100ah leisure batteries in my campervan. This works well, but it's expensive and takes up space.

Maybe get a spare battery and make sure both are charged before you leave!

Maybe that is the way forward. Thanks for taking the time to discuss

 

[flash]

So for us mere mortals who haven’t the foggiest how much would it cost to own the right battery abd be able to charge the bikes?

If I have the specs of your charger (what it wants for AC input) and how many charges you expect from the system I can give you an idea. But in short you need.

1. Battery. A 100aH AGM leisure battery should be fine for a single recharge. Lithium is a worthy upgrade for capacity, size and weight.
2. Inverter. Matched as closely as possible to the bikes charger.
3 Battery charger. You can recharge either from AC or from the vehicle while you drive. Solar is also possible but more complex.
4. A box to hold it all. Buy one or make your own.

Start at about GBP500 and move up for lithium and more capacity.

Gordon

 

[carlbiker]

If I have the specs of your charger (what it wants for AC input) and how many charges you expect from the system I can give you an idea. But in short you need.

1. Battery. A 100aH AGM leisure battery should be fine for a single recharge. Lithium is a worthy upgrade for capacity, size and weight.
2. Inverter. Matched as closely as possible to the bikes charger.
3 Battery charger. You can recharge either from AC or from the vehicle while you drive. Solar is also possible but more complex.
4. A box to hold it all. Buy one or make your own.

Start at about GBP500 and move up for lithium and more capacity.

Gordon

500 Bosch cheers

 

[flash]

500 Bosch cheers

OK. Your need 500 watts to charge your bike battery. That's about 39aH for a 12.8 volt battery. (39x12.8=498). Assuming you're using a cheaper AGM battery you need at least 80aH, as you should only use 50% of an AGM battery's capacity.

1. So you need an AGM battery that has 80aH capacity.

12v 85ah Leoch AGM Leisure Battery - Sunstore Solar

BATTERY IN BRIEF 12V 85Ah AGM Leisure Battery. Fit-and-forget AGM lead-acid battery for leisure & marine use – from Leoch’s Adventurer AGM range Features Absorbed Glass Mat technology (great durability and vibration-resistance) Totally sealed for life – dry-cell, unspillable and safe...

www.sunstore.co.uk

You need to be able to charge the aux battery. The cheapest way will be an AC battery charger that you plug in at home.

2. Battery charger. Found one on Amzon for 25 quid. Links don't want to work here.



Your standard charger needs 4 Amps (peak power) to run. You therefore need a 1000w inverter. (4 amps x 230 volts + 920 amps, plus some inefficiencies in the system = 1000 watt inverter.

3. Inverter.

Found one on Amazon UK for 75 Quid. Links don't want to work here.


All up about 400 quid for a basic system.

Gordon

 

[Andrie]

You need 300w inverter if you’re using Bosch 6A charger, even less with the 4A charger. I’ve done this, although on my last trip I did go with 1000W because I was charging 2 batteries at the same time.

there are advantages on running the smallest possible inverter. With 300A charger if you’re running 3’ or shorter cable you can get away with 10 gauge cables or 8 gauge if you’re running up to 10’.
If you’re running 1000W, you will need 4 gauge cables the least. I ended up with 2 gauge.

 

[Andrie]

Btw, Gordon calculation is actually wrong. You need at least 4A x 36v =144W.
As I mentioned I used 300W to charge using the 6A and it works fine. Cause I only needed 6Ax36v=216W.

Do not use cigarette lighter, not enough. You also need to install inline fuse if you are connecting your inverter directly to the battery. I’ve tested the 300W inverter to charge my Giant battery with 6Ax48v=288W and a 10 gauge wire gets warm, but still acceptable and you need 25A fuse.

 

[flash]

Btw, Gordon calculation is actually wrong. You need at least 4A x 36v =144W.
As I mentioned I used 300W to charge using the 6A and it works fine. Cause I only needed 6Ax36v=216W.

Do not use cigarette lighter, not enough. You also need to install inline fuse if you are connecting your inverter directly to the battery. I’ve tested the 300W inverter to charge my Giant battery with 6Ax48v=288W and a 10 gauge wire gets warm, but still acceptable and you need 25A fuse.

Depends if the 4A is the input amps or output amps. I wasn't able to find full specifications so assumed it was input amperage (AC power). As you say, if it's the output amperage your figures are accurate.

Gordon

 

[Shane(NZ)]

Btw, Gordon calculation is actually wrong. You need at least 4A x 36v =144W.
As I mentioned I used 300W to charge using the 6A and it works fine. Cause I only needed 6Ax36v=216W.

Do not use cigarette lighter, not enough. You also need to install inline fuse if you are connecting your inverter directly to the battery. I’ve tested the 300W inverter to charge my Giant battery with 6Ax48v=288W and a 10 gauge wire gets warm, but still acceptable and you need 25A fuse.

What car is that? Looks like a Tesla frunk?
What Giant has a 48v battery?

 

[routrax]

Btw, Gordon calculation is actually wrong. You need at least 4A x 36v =144W.
As I mentioned I used 300W to charge using the 6A and it works fine. Cause I only needed 6Ax36v=216W.

Do not use cigarette lighter, not enough. You also need to install inline fuse if you are connecting your inverter directly to the battery. I’ve tested the 300W inverter to charge my Giant battery with 6Ax48v=288W and a 10 gauge wire gets warm, but still acceptable and you need 25A fuse.

That's the output wattage. I think you need to be looking at the charger input.

My shimano is 2.5A input @ 240v, so 600w invertor

 

[jimbob]

That's the output wattage. I think you need to be looking at the charger input.

My shimano is 2.5A input @ 240v, so 600w invertor

With these chargers, it is probably easier to calculate from the output power. Because most of the chargers are designed to work over a range of voltages (100-250V), the current will be the maximum for the lower voltage go maintain the input power. For your example above, it is likley to be 100V x 2.5A, so 250W max, rather than 240V x 2.5A. Hope that makes sense?

They will also over rate the input current for the maximum possible. If you take your charger, for example, it runs at a maximum constant input power of ~85W (I've measured it). What you need to be careful of though is how the invertor is rated. A lot of them are not for continuous load which makes it a little harder to pick out the right one.

My advice (if you're not sure of the calculations) would be to go for a 500W invertor and connect directly to the battery.

 

[flash]

With these chargers, it is probably easier to calculate from the output power. Because most of the chargers are designed to work over a range of voltages (100-250V), the current will be the maximum for the lower voltage go maintain the input power. For your example above, it is likley to be 100V x 2.5A, so 250W max, rather than 240V x 2.5A. Hope that makes sense?

They will also over rate the input current for the maximum possible. If you take your charger, for example, it runs at a maximum constant input power of ~85W (I've measured it). What you need to be careful of though is how the invertor is rated. A lot of them are not for continuous load which makes it a little harder to pick out the right one.

My advice (if you're not sure of the calculations) would be to go for a 500W invertor and connect directly to the battery.

The problem here is that we're starting to discuss the complexities that most people don't want/need to hear about.

My Shimano charger is listed as 230-240V only (2.5A). Now it may run variable voltage but I can't take that chance when I make calculations. Conservative is good. Two of the three Bosch chargers in the UK/Oz are the same. They specifically mention the variable voltage charger which is the low amp charger. So I assume the 4 Amp charger is 230V only as mentioned in Boch's specs.

I know the 2.5A on my charger is peak. I know I have a 400W inverter that'll do 750W peak so it'll work with that charger. But I can't say that for somthing I find for a hundred quid on Amazon.

You are absolutely correct that the input power specifications for some inverters are for peak power and not continuous power. I have 2 2000W inverters. They run very differently as one is 2000W peak and the other is 2000W continuous. But without running them you wouldn't know because only one lists the difference. The problem is not all inverters list both peak and continuous ( two of mine do out of three.) so for making calculations it's far better to be conservative. The one I found above, under GDB100 was probably quoting peak power. So probably 500-650W continuous. Once you get to the difference between a 500W and 1000W charger the price difference isn't woth the samller one tripping at peak input.

But what's happening now is we're getting into the little details that make it confusing to those who are starting out. I was trying to keep it simple. 100aH battery, 1000 watt inverter. Charger. Go with that and I know it'll work. I can't say that about many cheap 500W inverters. I avoided direct to starter battery charger for a reason. Not all starter batteries can run high current deep discharge. I didn't want to get into cabling, current isolation, DC to DC chargers and smart alternators. I didn't want people stranded at the trailside. Same for solar. Not everyone can/is going to measure output current to work out their system. They just want a simple set up that'll work. Doesn't matter if it's a bit more than they need. As long as it's not less.

A bigger inverter also give room to expand. You never know what you might want to run in the future. Sometimes I take my Nespresso machine....

Gordon

 

[Andrie]

What car is that? Looks like a Tesla frunk?
What Giant has a 48v battery?

Yes that is Tesla Frunk. I just did 3 weeks road trip and always charge in the frunk.

I have Giant Reign E+ 1. The charger specify output of 48v.
Like I mentioned I also run 300w inverter in my Honda Element as I usually use that car and my finding is it’s good for one of those charger but not both.

 

[jimbob]

The problem here is that we're starting to discuss the complexities that most people don't want/need to hear about.

My Shimano charger is listed as 230-240V only (2.5A). Now it may run variable voltage but I can't take that chance when I make calculations. Conservative is good. Two of the three Bosch chargers in the UK/Oz are the same. They specifically mention the variable voltage charger which is the low amp charger. So I assume the 4 Amp charger is 230V only as mentioned in Boch's specs.

I know the 2.5A on my charger is peak. I know I have a 400W inverter that'll do 750W peak so it'll work with that charger. But I can't say that for somthing I find for a hundred quid on Amazon.

You are absolutely correct that the input power specifications for some inverters are for peak power and not continuous power. I have 2 2000W inverters. They run very differently as one is 2000W peak and the other is 2000W continuous. But without running them you wouldn't know because only one lists the difference. The problem is not all inverters list both peak and continuous ( two of mine do out of three.) so for making calculations it's far better to be conservative. The one I found above, under GDB100 was probably quoting peak power. So probably 500-650W continuous. Once you get to the difference between a 500W and 1000W charger the price difference isn't woth the samller one tripping at peak input.

But what's happening now is we're getting into the little details that make it confusing to those who are starting out. I was trying to keep it simple. 100aH battery, 1000 watt inverter. Charger. Go with that and I know it'll work. I can't say that about many cheap 500W inverters. I avoided direct to starter battery charger for a reason. Not all starter batteries can run high current deep discharge. I didn't want to get into cabling, current isolation, DC to DC chargers and smart alternators. I didn't want people stranded at the trailside. Same for solar. Not everyone can/is going to measure output current to work out their system. They just want a simple set up that'll work. Doesn't matter if it's a bit more than they need. As long as it's not less.

A bigger inverter also give room to expand. You never know what you might want to run in the future. Sometimes I take my Nespresso machine....

Gordon

Agree with everything you say. I guess you're correct that its dangerous to over simplify this subject, especially as there are so many cheap investors out there which aren't clear on their specifications.

Just for interest, I have just checked my Shimano E6002 and its rated for 100-240V input.

 

[Mr President]

charging from a 12v inverter - some details

Hi All I've wondered for a while about charging the my Whyte E160 from a car battery via an inverter. I've seen a few posts discussing, but nothing really about whether it has been successful or not, except for those who are lucky enough to have full on RV set-ups. I just wanted to be able on...

www.emtbforums.com

see above thread.

I should probably have posted here, but this one was getting very mathematical. Just wanted to simply state what I have done and how well it works.