Reusable Batteries - Types and Maintenance

18.11.20: There are times when I wonder what each type is best for and how best to maintain adequate life.
It took quite some time to compile these characteristics for standard rechargeable battery types, as companies appear to want to keep the details to themselves.
As you can see, in the chart, I couldn't find everything I wanted for Alkaline and Lead Acid.
Each battery type has a specific or best use device.
Some battery types can be used in the same device.
IMO, always try to purchase a Li-ion battery for your device. 

The Bottom Line:
Rechargeables are the best approach for the future.
Check which batteries can be used in a device, BEFORE buying.
Check which types of batteries can be used in your recharger, BEFORE buying.
Review when to recharge the batteries, BEFORE buying.

It might be important to know which type of battery is used in home phones, cell phones, laptop computers, flashlights, etc). I have identified a few at the end of this blog item.

Here is my analysis/summary of reusable batteries.
The types are: 

- Alkaline (RAM) 
- Lithium ion (Li-ion) 
- Nickel Cadmium (NiCd) 
- Nickel-Metal Hydride (NiMH) 
- Sealed Lead Acid (SLA) 

A brief word on alkaline batteries. They are not rechargeable (unless stated) and alkaline are the only true 1.5V battery. They are environmentally unfriendly and the cheapest  to buy but should only be used if no other alternative will work.
Rechargeable alkaline battery (as with all rechargeables) have a better ROI (return on investment).  

Each battery type has specific characteristics that should be considered when thinking about purchase and replacement.

Most standard alkaline devices will work with NiCd and NiMH rechargeables. 

The following information will help you make the purchase correctly.

- Alkaline are very low usage:
In the small round battery arena, rechargeable alkaline is a very good selection but Li-ion is the best selection
The chart has a few missing alkaline entries but the important characteristic is 1.5V. Other rechargeables (not Li-ion) are not as strong and may not work or work as well as rechargeable alkaline (such as battery toothbrush).

- NiCd batteries have a memory: 
If you DO NOT continue to use until discharged (device slows) before recharging, the battery will not last as long as it could and will eventually not last more than a few minutes.
They should be used regularly and fully discharged (until device stops), to ensure memory shortage is less likely.
They are high capacity rechargeables, cheapest, fastest to recharge but most environmentally unfriendly.

- NiMH do not have a memory:
You can put them in a recharger anytime and leave them there...no memory.
They are slightly better than NiCd (see chart).
While you can do it, it is best not to overcharge (leave it in the charger) when not using. 

- Li-ion are probably the best rechargeable battery: 
There the thinnest and lightest and have the most recharge cycles. 
They are the only rechargeable that can be placed in the recharger anytime and left as long as you like.
They are the only batteries to be used in smartphones and anything using a button battery.
Warning - battery stops working if left outside in very cold weather. 

- SLA are the heaviest:
Lead Acid batteries (like ones used in your car) are cheap, safe, durable and dependable. They can be placed in a recharger anytime. They aren't used as much now and are mainly used for Backup Generators, older Lawnmowers, older snowblowers and golf carts. High voltage Li-ion are quickly replacing them because -as with the incandescent light bulb - they are very environmentally unfriendly and can only be recharged 1/4 the times.

How does power (V) and longevity (Ah) increase in a battery type?
Most rechargeable battery types come in a few power and longevity variations. All batteries are made up of cells. See the charts for V (voltage) for a cell of each battery type.
To increase power, the cells are connected in series (+ to - and - to +). 
To increase longevity (time between recharges), the cells are connected in parallel.

What batteries are in standard devices we use daily?

- Laptop computers mainly use Li-ion batteries but detachable ones do lose memory over time if you do not detach them while plugged into household current. Always fully charge and then take out (if you can) if household current is being used. 
The newest laptops do not have detachable batteries. They are protected against memory loss. Always check before buying and understand how to treat your non-detachable battery.

Digital Cameras and cell phones have Li-ion batteries. Most devices requiring a flat battery use Li-ion.

- Most LED flashlights and toothbrushes all best with rechargeable alkaline and li-ion batteries. 

- Home phones use NiCd and NiMH and some may now use Li-ion. It is important to know what is used to ensure protection against memory loss.
Panasonic phones (IMO, the best available, if you must use a home phone) are MiMH and advise only placing in the holder (recharger) at night.     

- Power tools use all three types of rechargeables. The newer tools (most expensive with smaller battery packs) are Li-ion and higher voltage (20 and higher) last longer but are even more expensive. 

Remember, if not Li-ion, use the tool until it loses noticeable power before recharging.

- Cordless lawnmowers and snowblowers require more voltage. My cordless lawnmower is only 24V (SLA) but still holds a good charge for the whole property after 6 years. They now have 80V (Li-ion) snowblowers and lawnmowers (my next one) and snowblower. Just remember to store a snowblower battery (Li-ion) indoors in cold weather. 
Leafthrowers/vacuums are a different issue as they need to be smaller and light (Li-ion) but powerful. After much research, I bought a corded instead of cordless, as cordless are not strong enough yet.

- Golf Power Carts are either SLA (older and much heavier) or Li-ion (all new ones and much lighter).  

Rechargeable battery chargers:
They can be different for battery makers and battery types.
Always check what types of batteries can be recharged, BEFORE MAKING THE CHARGER PURCHASE.

If you have a question or would like to add information, pls comment.