Black Friday LifePo4

tee_cee · 2023-11-22 21:22:33

Some decent prices at Fogstar until Monday.

kenbw2 · 2023-11-23 01:54:20

Oh wow yea, this one's a very good price: https://www.fogstar.co.uk/collections/l … rift-105ah

Even has an inbuilt heater for sub-zero charging

tee_cee · 2023-11-23 20:22:01

Yes, the heating is nice to have, as is UK support. I recon that 2 105ah would fit under the passenger seat. However the 230ah under seat will too. So I went for it.
It's a lot to spend, but long term it will be cheaper, and has a better chance of actually being useable.

Last edited by tee_cee (2023-11-23 20:29:19)

kenbw2 · 2023-11-23 23:51:48

Yea I went through plenty of lead-acids, including AGMs, before I caved the hundreds on the LiFePO4. Well worth it, still going after 3 years of daily cycling.

I managed to get it in the engine bay between the (tiny) starting battery and the air filter. Only just fits under the bonnet!

tee_cee · 2023-11-24 09:56:07

Do you charge via the alternator at all. These seen to present a huge load when charging!

kenbw2 · 2023-11-24 20:05:43

Yea I just hooked it up with an engine-running relay, never had an issue. I've actually had a meter between the two and it charges at a couple of hundred watts - so maybe 10 amps max. But it quickly tails off as the battery voltages equalise

kenbw2 · 2023-11-25 00:55:12

Reminds me, I should unplug my solar tonight - I've seen enough Will Prowse videos to not believe my battery's claim of low temp charging protection

tee_cee · 2023-11-25 11:42:07

I'm surprised that you are only drawing 10A, assuming that it is a 100AH, I'd expect it to draw 30-50. My new 230AH is rated at a whopping 200A max charging so I'm a bit scared of doing some damage to my alternator, even though it's probably rated at 150A.
I have ordered a 40A b2b charger. Aside from the extra cost, these things are huge.
Hope it didn't get too cold last night :-)

kenbw2 · 2023-11-26 02:18:52

tee_cee wrote:

I'm surprised that you are only drawing 10A, assuming that it is a 100AH, I'd expect it to draw 30-50. My new 230AH is rated at a whopping 200A max charging

Yea mine had a max rating of somwhere around 70A, and I prepared the setup to handle that but I never saw it happen. I think I blew a 10A fuse once, but again that's only on the initial hit before the voltages equalised. Never blown a 30A fuse

tee_cee · 2023-12-14 17:33:31

As a footnote, the battery did not actually fit under the seat. I missed out the mechanism used to release the seat back/forward. I could have squeezed it in, but I did not like the idea of metal (grounded) parts being so close to the +ve terminal. I was lucky enough to have enough room behind the seat, and I still fit a 1000W inverter, and 40A DC-DC charger under the seat.

kenbw2 · 2023-12-14 21:48:02

I often hear of people using DC-DC converters for alternator charging. What made you choose that over just exposing the battery to the alternator's 14.4V?

tee_cee · 2023-12-15 12:29:16

A few reasons.

My "smart" alternator will charge up to 14.9V, or down to 12.7V if it feels that the battery is ok.
At half charge my battery is reading 13.1V, so I guess the alternator could settle at 12.7V - so no charging. If it does carry on charging at 14.9V, once the battery hits 14.2-14.4V, the BMS will shut the battery off. The general chat would suggest that this can cause a sharp voltage spike at the alternator - and consequently all of your 12V electrics. Current draw is also a concern. The battery will accept up to 200A, and my alternator is probably 150A. So I would need to install some beefy cable to cope. Also there is a video that shows an alternator smoking, at low revs, due to insufficient cooling. Though it was made by Victron, who would really like to sell a DC-DC converter to you.

Ultimately I chickened out and bought a DC-DC converter, because there are just too many unknowns, and the risk of damage is probably real.

kenbw2 · 2023-12-15 23:46:39

Ah your alternator is way more smart than mine. Nothing smart at all about my van haha

tee_cee · 2023-12-17 18:15:49

Smart eh.. Just another black box that the end user has no idea whats going on. One think I can tell is that a lot of whats going on is to convince the regulators that it likely to be less polluting. So when parked up my radio stops working after 15mins, to save the battery, forcing me to run the engine to listen for a few more mins. Same if I want to wind the windows up. Thats progress for you.

kenbw2 · 2023-12-17 19:05:48

I was so glad when I hooked my stereo up to the house battery, used to drive me insane that it would turn off and confuse my Bluetooth conenction when I cranked the engine

tee_cee · 2024-02-03 15:55:27

Had a look at my radio again, and it won't even switch on without the canbus, so no point in hardwiring it to the leisure battery. :-(

Pathfinder100 · 2024-02-18 14:43:31

Throw a cheapo chinese head unit in with Bluetooth and use that when the main one decides to shutdown. If all you want is to listen to the radio or maybe play MP3's from your phone, it doesn't need to be an all singing and dancing system. Just a couple of small speakers and a cheap unit. Or the low tech version that i use, is a £16 home bargains bluetooth speaker connected to a USB port on the shelf above my head, when driving. It does radio and it does bluetooth for the phone. smile

kenbw2 · 2024-02-18 20:39:38

The Dispatch | Expert | Scudo Hub

Get help & share your Citroen Dispatch (Jumpy) | Peugeot Expert | Fiat Scudo tips

#1 2023-11-22 21:22:33

Black Friday LifePo4

#2 2023-11-23 01:54:20

Re: Black Friday LifePo4

#3 2023-11-23 20:22:01

Re: Black Friday LifePo4

#4 2023-11-23 23:51:48

Re: Black Friday LifePo4

#5 2023-11-24 09:56:07

Re: Black Friday LifePo4

#6 2023-11-24 20:05:43

Re: Black Friday LifePo4

#7 2023-11-25 00:55:12

Re: Black Friday LifePo4

#8 2023-11-25 11:42:07

Re: Black Friday LifePo4

#9 2023-11-26 02:18:52

Re: Black Friday LifePo4

#10 2023-12-14 17:33:31

Re: Black Friday LifePo4

#11 2023-12-14 21:48:02

Re: Black Friday LifePo4

#12 2023-12-15 12:29:16

Re: Black Friday LifePo4

#13 2023-12-15 23:46:39

Re: Black Friday LifePo4

#14 2023-12-17 18:15:49

Re: Black Friday LifePo4

#15 2023-12-17 19:05:48

Re: Black Friday LifePo4

#16 2024-02-03 15:55:27

Re: Black Friday LifePo4

#17 2024-02-18 14:43:31

Re: Black Friday LifePo4

#18 2024-02-18 20:39:38

Re: Black Friday LifePo4

Board footer