817/8 modern battery solutions

I have recently bought a 817nd getting back into hf, in past i had sone 4s lifepo4 batteries but i gave them away .

Im finding it hard to find 4s lifepo4 battery around 5 - 7ah .

Yes can go 3s lipo , i operate on 2m fm quite a bit also so concerned on a 3s i would drain them quite rapidly.

Wondering if any more up to date battery solutions?

1 Like

In my opinion, the 2.5Ah 3S 11v flat battery, that fits inside the radio (when you make up the wiring harness) is the best all-round solution avoiding having to have an external battery at all. This has been documented and discussed several times on this reflector. You can either do it yourself with a LiPo battery from Hobby King (if they still ship to the UK) or buy a complete kit out of the US (which may be available through one of the UK retailers).
Here’s the link to the battery at Hobbyking (but its out of stock!):

If you particularly want the larger external LifePO4 battery, I’m surprised you say you are finding it difficult to find them. Here is Germany the “goto company” is Eremit, but he doesn’t ship to the UK. I had thought a lot of the sports / electrical outlets in the UK would have 4-6Ah (and larger) LifePO4 batteries available (ideally with a BMS built-in).

73 Ed DD5LP

1 Like

Internal: I made 2 packs from recycled vape batteries, still working a treat
image

External: As recommended by @MM0FMF I acquired a brand-new Dell laptop battery from the bay at 99p plus postage. Stripping out the 18650 Li-on cells I made a 3S2P 12V 4.4 Ah pack with a balancer board for under a tenner all in.

Rick

3 Likes

There does seem to be real shortage of these items now, especially the RC power packs.

As Ed says, the Eremit packs are LiFePO4 packs made from multiple 18650 sized cells with a full BMS. Absolutely brilliant packs but you will not be able to get it shipped to the UK. You will have to get it shipped to someone you know on mainland EU and then figure out how to get it from them. Ed is also right that bigger LiFePO4 packs, 12Ahr are available from Amazon from £60.

Whilst LiFePO4 is a big improvement on LiPo, 3S LiPos can stil be had for a good price, they’re just not as safe as LiFePO4. Hobbyking has a better range of these than LiFePO4 right now. This offer from Amazon looks interesting… Amazon.co.uk especially as you could run them in parallel for endurance. 817 is happy for the voltage to fall low before output drops. £22 +P&P for 2 is a damn good deal, I don’t know if the cells are any good or not.

Both myself and Rick have had some good results with recycling batteries from disposable vapes and old laptop packs. Rick’s pack pictured shows an 11.1V 2Ahr pack made from vape batteries with 3D printed case. I have a 1.1Ahr and 1.5Ahr pack made from vapes that I use with my QCX radios. Also I have about 15 18650 LiPo cells (1.8Ahr, 2.5Ahr) recovered from old laptops. With a 3x 18650 holder from eBay these have been used many times to power my old 817 and now a KX2.

So there are plenty of solutions but it’s just a bit more involved than say 5 years ago.

2 Likes

That’s cool. Is there a particular battery type to look for ? I was assuming most are flat LiPo not containing 18650’s

Thanks in advance
Tim

2 Likes

Hi Tim

They mostly seem to still have 18650’s - I think they are cheaper and more reliable for the manufacturers, and they aren’t too bothered about the weight.

I got an MC34Y, that fits some of the older Latitude models

Something like this might suit

EDIT Oops I think those are actually LiPo

Rick

2 Likes

Yes, older packs that have some thickness to them. From about 2014 onwards the higher end machines became very thin with removal thin packs that obviously cannot contain an 18650. Then they stopped fitting removal batteries. Now some will have soldered batteries to force you to buy a new machine not fix it.

This new pack is the right shape New Laptop Battery for Dell 1525 1526 1545 1546 1750 1440 PP29L PP41L, Fits P/N | eBay

I found out on Wednesday one of our contesting group has bought a battery welder for making proper packs up. So I should be welding some packs together in the next few weeks.

3 Likes