Battery jump starters

[WTFH]

I tried one of them (a 5 Watt version). It didn't even keep the battery fully charged in summer but would have been hopeless in winter. The windows in my car are slightly tinted, and this greatly reduces the power output of the panel.

See the one mentioned in my post above. It was recommended to me and it works, even with tinted windows.

[d000hg]

Well anyway it turns out our battery was just dying/knackered. Over £200 to have a new one... fancy stop-start tech means it's a fancy one apparently.

That NOCO is one I'd seen before and if it's something mechanics use that's a good sign. Have to make sure it stays charged though!!

Here's a question - why do cars still use huge heavy Lead-acid batteries? Is it possible to get a Lithium as you main car battery these days?

[WTFH]

Is it possible to get a Lithium as you main car battery these days?

Yes, but at a cost...
https://www.roadpro.co.uk/product/02...re-c9465/C9465

[DealorNoDeal]

See the one mentioned in my post above. It was recommended to me and it works, even with tinted windows.

What's the longest you've ever left your car without starting it? Have you checked the battery voltage after the car's been left standing for a few days?

A sign that the solar panel isn't keeping it fully charged would be if the voltage drops a little bit each day. Ideally, it should be maintaining it at very close to 12.6V. I'd be a bit sceptical of it achieving this in the middle of winter.

A car alternator can very quickly recharge a battery, so it's possible you've just been lucky. I got caught out with a flat battery several times, which is why I rigged up a mains trickle charger.

[d000hg]

Well it doesn't need to stop the battery draining completely, only slow it down to the point the car will start however often you drive it.

Another thing I find odd is that cars don't tell you your battery status. Ours gave us "battery flat" at the point it wouldn't start which was no help at all. The garage today had a simple test unit and our home charger is smart enough to work out the battery health and figure a charging cycle... why not build one of these into the car?

[DealorNoDeal]

Well it doesn't need to stop the battery draining completely, only slow it down to the point the car will start however often you drive it.

The battery will deteriorate if you do that. To get a decent life out of a car battery, you need to keep it fully charged at all times. If you use the car every day, for reasonable length journeys, then the alternator will do this. If, like me, you only use it a couple of times a week, then a trickle charger is the best solution. I haven't had to buy a new battery for 9 years since I hooked it up to a trickle charger.

[WTFH]

The battery will deteriorate if you do that. To get a decent life out of a car battery, you need to keep it fully charged at all times. If you use the car every day, for reasonable length journeys, then the alternator will do this. If, like me, you only use it a couple of times a week, then a trickle charger is the best solution. I haven't had to buy a new battery for 9 years since I hooked it up to a trickle charger.

Garbage.

You cannot keep a battery fully charged at all times if you want to drive the car on normal journeys. A journey of less than half an hour, slower driving, driving with heated seats etc on will make it difficult to recharge a battery fully.
You'll also notice that not everyone in the world has a flat battery all the time.

Perhaps your home made trickle charger is great, in that it covers temperature variation, desulphation, conditioning etc. If it doesn't then maybe refer to my earlier post where I mentioned the MXS 5.0 from CTek.

Here's a few useful references for those of us who don't it know all:
https://www.victronenergy.com/live/drafts:battery_life
https://batteryworld.varta-automotiv...ttery-charging

[DealorNoDeal]

Garbage.

I'm an electrical engineer. What's your qualification?

You cannot keep a battery fully charged at all times if you want to drive the car on normal journeys. A journey of less than half an hour, slower driving, driving with heated seats etc on will make it difficult to recharge a battery fully.
You'll also notice that not everyone in the world has a flat battery all the time.

Do you know how many Amps an alternator pumps out? It will recharge a battery very quickly. The battery is only for starting the engine. Once the engine is running, you could disconnect the battery because the alternator will power everything.

Sure, if you only do very short journeys every day, it can be problematic. But there's a reason why most people who drive every day hardly ever have battery problems.

Perhaps your home made trickle charger is great, in that it covers temperature variation, desulphation, conditioning etc. If it doesn't then maybe refer to my earlier post where I mentioned the MXS 5.0 from CTek

Well, it's kept my current battery tip top for over 9 years, so I'm not about to fix what ain't broken.

[DealorNoDeal]

Perhaps your home made trickle charger is great, in that it covers temperature variation, desulphation, conditioning etc. If it doesn't then maybe refer to my earlier post where I mentioned the MXS 5.0 from CTek.

Does your solar panel do any of that? Does the car's alternator electronic circuit do any of that? Nope.

I'm not saying it's total BS but I imagine it's what sells what is a relatively expensive piece of kit.

Imagine if Dyson built a car battery charger.

[WTFH]

Do you know how many Amps an alternator pumps out? It will recharge a battery very quickly. The battery is only for starting the engine. Once the engine is running, you could disconnect the battery because the alternator will power everything.

Sure, if you only do very short journeys every day, it can be problematic. But there's a reason why most people who drive every day hardly ever have battery problems.

So if the alternator will fully recharge the battery very quickly, then why do journeys of less than 30 mins not charge it? And since when was a 30 minute journey "very short"?
Also, given your knowledge, sitting in slow moving traffic in winter with heated seats on, heated steering wheel on, heated windows on, A/C pumping away - is the alternator still putting out enough to keep those going AND recharge the battery fully?

Yes, I agree that if a car is being driven on longer journeys regularly, it is not an issue, but not everyone does the same driving you do, so as the saying goes YMMV.