Buy Your Friends Batteries

https://domenkozar.com/2026/08/17/buy-your-friends-batteries/

26•domenkozar•42m ago

Comments

wheatone•36m ago

May as well be "Buy Your Friends Bombs." given what we've seen with Israel's pager-bomb operation in the MidEast.

Where do people store these things? They're very dangerous once afire! Worse than a can of petrol by far and can't be extinguished with water.

domenkozar•23m ago

This battery uses a safer type of lithium chemistry that is less prone to overheating, though no large battery is risk-free. Water is used by firefighters to cool battery fires (they can reignite tho).

Install it outdoors or in a detached garage, away from anything flammable. Never in a bedroom, hallway, or escape route.

There are newer batteries tech that can't inflame.

beaviskhan•19m ago

Most modern batteries like this are weatherproof and can be mounted outside the home. Most modern batteries use LiFePO4 chemistry, which while not perfect, is much less risky in terms of thermal runaway than older lithium ion batteries.

fhdkweig•13m ago

The Tesla Powerwall is only slightly larger than a pizza box and can be mounted directly on the wall. Most of the below images are outside the house, but some are also in the garage.

https://duckduckgo.com/?q=tesla+powerwall&ia=images&iax=imag...

thejazzman•11m ago

Tesla powerwall is 44” x 24”

Where are you buying your pizzas?!

toomuchtodo•30m ago

Great piece and post, love the concept!

domenkozar•23m ago

Let's go!

Retr0id•23m ago

> Create a battery birthday club. Buy each friend a battery on their birthday until everyone has one.

At that point, wouldn't it be easier if everyone just bought their own? And then whoever has the latest birthday doesn't have to wait a year to get theirs.

domenkozar•18m ago

That's step one, next is your friends.

cbarnes99•16m ago

I think the point is that breaking it up makes the cost more palatable. It's also easier to convince people to spend a bit of money for people they care about than a bunch for themselves that they don't strictly need. People also often struggle to think of gift ideas for birthdays.

oytis•11m ago

But then you still have to buy birthday presents on top of that

Retr0id•8m ago

If everyone's giving everyone the same gift, it's not really a "gift" any more, more of a p2p buy-now-pay-later arrangement (which isn't a terrible idea, but it's suboptimal for those with later bithdays).

blitzar•4m ago

Might as well just have an annual theme every year and try to negotiate a bulk discount.

Apreche•18m ago

Anyone who can afford to own a home can afford their batteries and doesn’t need gifts. Renters are not allowed to modify their home in such a way.

well_ackshually•17m ago

>sixteen people contribute €100 each;

yeah sure everyone has 100€ to spend on friends, at least once a month.

What kind of reality does he live in ?

isoprophlex•17m ago

> You are also safer during a power outage. The STREAM 5000 provides up to 3 kW of off-grid output. Keep essential devices on its backup output and reserve some battery capacity, and your refrigerator, lights, router, and laptop can keep running when the grid goes down. An ordinary grid connection does not back up the whole house automatically; the backup output must be configured correctly.

Being able to cut over your entire house from grid power to a battery requires an invasive, expensive change to most connections. I wish people would stop breathlessly promoting batteries (which are good! we need decentralized storage!) because "you can use them to run your fridge, router, etc". Yes you can, but for almost all consumers it's an order of magnitude more effort and cash compared to just buying and plugging in a battery.

fhdkweig•10m ago

If a fridge is your only concern, they make UPSes specifically for fridges.

https://duckduckgo.com/?q=Uninterruptible+power+supply+refri...

tonymet•10m ago

I disagree. During an outage, you need your fridge and a few other essential items. A novice can plug into the back. The device tells you the load and whether you are exceeding. And you can test it at any time. For $600 you can get started without an electrician.

it's the easiest, safest , most affordable and most reliable emergency solution ever available.

brk•3m ago

For a relatively small battery like that, it's not going to last for days. In the typical outage where that battery would carry you, you can typically just leave the fridge closed and it will stay cold enough to prevent 99% of your stuff from spoiling. For most people (at least the US), it's not super easy to get at the plug in the back of the fridge anyway.

Running HVAC is usually more of a concern, especially in winter or peak of summer, and those aren't device that you can hot-plug, and a small battery wouldn't help there anyway.

I like the idea of whole-house batteries, but to really make it practical you're talking about thousands of dollars to the battery, install, etc. And you still don't have extensive run time, which is why I think you see most people still leaning towards permanent or portable generators way more than batteries.

or_am_i•16m ago

How does 12 years required for this scheme to pay for itself stack up against the typical house battery's lifetime?

strbean•12m ago

Sounds like that's roughly the average usable lifetime for the battery, so you will break even on average.

Retr0id•10m ago

Also, as more batteries get added to the grid, the difference between the "cheap" and "expensive" energy prices ought to reduce.

jerlam•15m ago

> 2. Confirm that their home, meter, and electricity contract are compatible.

This seems like the hardest step. The costs of "just a battery" are much lower by comparison.

archydeb•5m ago

And if you’re in the UK, wire them up to Axle Energy

(plug-in batteries aren’t actually legal here yet, but likely to become so next year!)

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